[Multi-grid]

On Nov 6, 3:15 am, Andre Jute wrote:
On Nov 5, 10:42 pm, John Byrns wrote:





In article . com,

Multi-grid wrote:
On Nov 4, 4:43 pm, Andre Jute wrote:

They're your words and they don't make sense to me. Take all the space
you need. Please feel free to treat me as a total ignoramus and
explain in words of one syllable, with all the tees crossed and all
the eyes dotted so that there can be no misunderstanding.

Considering this request, I must know how it is you can judge it so
surely. I am left with three choices: you're incompetent or nasty
without bound, or both.

looks more and more like the latter.



A schematic
is always good to avoid misunderstanding.

What don't you 'get'? Think some more. Think 'ampere-turns'. Take a
primary of two to three thousand turns, and run 100 mA through it. Put
this coil around a minimum gap/alternate stacked E-I or cut C-core.
What happens to the flux?

Got an answer yet?

Take another winding, and run the filament current through it. It is
substantially larger than 0.1 Ampere( actually 25 A was my example).
You should energize the correct end of this winding, eh?

Andre, notice how Multi-grid is avoiding your question, and being
evasive about how this scheme actually works. It is straight forward to
use the filament current to provide the bias to the core to offset the
current from the amplifier tube, or any other current for that matter,
as long as the number of ampere-turns is the same as in the active
primary, as Multi-grid points out.

Yes, but that means a specially wound transformer, a vast expense in
the context of trying to use a junkbox or at least existing PP
transformer for SE.

Why are you misrepresenting my claim? I never represented it in any
way save for its performance. The OPT was not a major expense though.
It can be done inexpensively, but I will excuse myself until you show
more appropriate manners.


Plus a cap and probably a choke that Multi-Cuddles
doesn't mention, and soon you're into real money. This isn't an
innovation, this is a kludge to bodge right another kludge.

Where do you get these wonderful ideas?



Unfortunately the issue that
Multi-grid doesn't want to deal with, or can't, is that a substantial
portion of the audio power generated by the active tube is dissipated
across the filament resistance of the tube and never makes it to the
speaker.

Yah. This is why I wrote to Robert Casey that I have zero faith in
these heathrobinson schemes because I have never managed to run more
than a tiny fraction of the PP current through a PP trx being used for
SE, not if I wanted a result that satisfied my noise criteria anyway.
It's a novelty, not a circuit.

The bottom line is that this circuit doesn't work very well when built
as Multi-grid describes it.

Pretty confident for one who hasn't heard or seen it...typical closed
minded tripe though.


The problem can be dealt with, but dealing
with it adds considerable extra cost, which makes one wonder why anyone
in their right mind would take this approach to building an amplifier in
the first place?

At the time that Bottlehead took his Electronic Tonalities all-
parafeed, he said it was because it sounded better. I believe him,
that it sounds better to him and his circle of very competent DIYers.
But I like conservative engineering, especially KISS. I'd rather spend
the same money that goes into parafeed on a proper SE output and just
put the bloody current through the primary.

No arguement there. You miss a few other important shortfalls. You'll
figure them out sooner or later I suppose...
cheers,
Douglas

[Andre Jute]

WTF is this, Cuddles? We've given you multiple chances to tell us what
you're talking about or, better still, show us a schematic but you're
as unbelievably coy as a whore at a sailor's stag night. Just show us
the schematic and let us work it out.

Andre Jute
Patience isn't my best talent


On Nov 6, 2:03 am, Multi-grid wrote:
On Nov 6, 3:15 am, Andre Jute wrote:

On Nov 5, 10:42 pm, John Byrns wrote:

In article . com,

Multi-grid wrote:
On Nov 4, 4:43 pm, Andre Jute wrote:

They're your words and they don't make sense to me. Take all the space
you need. Please feel free to treat me as a total ignoramus and
explain in words of one syllable, with all the tees crossed and all
the eyes dotted so that there can be no misunderstanding.

Considering this request, I must know how it is you can judge it so
surely. I am left with three choices: you're incompetent or nasty
without bound, or both.

looks more and more like the latter.

A schematic



is always good to avoid misunderstanding.

What don't you 'get'? Think some more. Think 'ampere-turns'. Take a
primary of two to three thousand turns, and run 100 mA through it. Put
this coil around a minimum gap/alternate stacked E-I or cut C-core.
What happens to the flux?

Got an answer yet?

Take another winding, and run the filament current through it. It is
substantially larger than 0.1 Ampere( actually 25 A was my example).
You should energize the correct end of this winding, eh?

Andre, notice how Multi-grid is avoiding your question, and being
evasive about how this scheme actually works. It is straight forward to
use the filament current to provide the bias to the core to offset the
current from the amplifier tube, or any other current for that matter,
as long as the number of ampere-turns is the same as in the active
primary, as Multi-grid points out.

Yes, but that means a specially wound transformer, a vast expense in
the context of trying to use a junkbox or at least existing PP
transformer for SE.

Why are you misrepresenting my claim? I never represented it in any
way save for its performance. The OPT was not a major expense though.
It can be done inexpensively, but I will excuse myself until you show
more appropriate manners.

Plus a cap and probably a choke that Multi-Cuddles

doesn't mention, and soon you're into real money. This isn't an
innovation, this is a kludge to bodge right another kludge.

Where do you get these wonderful ideas?



Unfortunately the issue that
Multi-grid doesn't want to deal with, or can't, is that a substantial
portion of the audio power generated by the active tube is dissipated
across the filament resistance of the tube and never makes it to the
speaker.

Yah. This is why I wrote to Robert Casey that I have zero faith in
these heathrobinson schemes because I have never managed to run more
than a tiny fraction of the PP current through a PP trx being used for
SE, not if I wanted a result that satisfied my noise criteria anyway.
It's a novelty, not a circuit.

The bottom line is that this circuit doesn't work very well when built
as Multi-grid describes it.

Pretty confident for one who hasn't heard or seen it...typical closed
minded tripe though.

The problem can be dealt with, but dealing

with it adds considerable extra cost, which makes one wonder why anyone
in their right mind would take this approach to building an amplifier in
the first place?

At the time that Bottlehead took his Electronic Tonalities all-
parafeed, he said it was because it sounded better. I believe him,
that it sounds better to him and his circle of very competent DIYers.
But I like conservative engineering, especially KISS. I'd rather spend
the same money that goes into parafeed on a proper SE output and just
put the bloody current through the primary.

No arguement there. You miss a few other important shortfalls. You'll
figure them out sooner or later I suppose...
cheers,
Douglas

[Multi-grid]

On Nov 6, 4:20 am, Andre Jute wrote:
WTF is this, Cuddles? We've given you multiple chances to tell us what
you're talking about or, better still, show us a schematic but you're
as unbelievably coy as a whore at a sailor's stag night. Just show us
the schematic and let us work it out.

Andre Jute
Patience isn't my best talent


I offered a starting point, and you ignored it. Then you asked for
detail.

My response remains: you'll need to do some of the work yourself.
You'll learn more, and it will be less work for me.

Now if it is of interest, prove it and start answering my ground work
understanding questions instead of pronouncing it, "a kludge to bodge
right another kludge".
cheers,
Douglas

[Patrick Turner]

Andre Jute wrote:

WTF is this, Cuddles? We've given you multiple chances to tell us what
you're talking about or, better still, show us a schematic but you're
as unbelievably coy as a whore at a sailor's stag night. Just show us
the schematic and let us work it out.

Andre Jute
Patience isn't my best talent


I have been rather busy as usual trying to eek a living from making
exoticly simple and effective amplifiers,
or converting horridly complex piles of yank junk into paradimes of
sonic virtue.

This thread has rapidly become obtuse to the nth degree,
with only an inner circle able to out-imaginatize each other with
wordolgies
that are relevant only for the 10 seconds the few ppl involved have them
in their minds.

I kinda feel I ain't missing out on much by not following it along.

Who was Duggy? Douglas Fartentuber perhaps? He was an outstandingly
inovative European
in the 1950s, invented all this stuff but the yanks copied and patended
his ideas as their own...
But not the brighter ideas about SE though.
Out of sight and out of mind, the Japanese matured their ideas about SE
for about 47 years
until about 1992, when "western" nations suddenly realised there was
some new candy
thay had missed out getting......
I'd never know Japan had ever existed from reading this group.
In the US, consciousness of European existance is all very limited......


Of course the group SHOULD be allowed to show binaries up to say 50kB,
and so .GIFs of schematics would be wonderful rather than having to read
them at
ABSE, where in this country the arsole boffins controlling the Internet
access
make sure you can't see the binaries posts from ABSE. I protested about
it to my ISP
and it was like having a discussion with a dead cat.


What could be done to allow minor binaries r.a.t
?????????????????????????????????????????????????? ??


In the past, one Basset, a mainly horrible man who poses as a dog posted
a .jpg here of his doghouse.

It was not blocked out. He did an earlier image as well...

Patrick Turner.



Snip miles and miles of blahdiddleyah...

[Patrick Turner]

Multi-grid wrote:

On Nov 6, 4:20 am, Andre Jute wrote:
WTF is this, Cuddles? We've given you multiple chances to tell us what
you're talking about or, better still, show us a schematic but you're
as unbelievably coy as a whore at a sailor's stag night. Just show us
the schematic and let us work it out.

Andre Jute
Patience isn't my best talent


I offered a starting point, and you ignored it. Then you asked for
detail.

My response remains: you'll need to do some of the work yourself.
You'll learn more, and it will be less work for me.

Now if it is of interest, prove it and start answering my ground work
understanding questions instead of pronouncing it, "a kludge to bodge
right another kludge".
cheers,
Douglas

Hmm, how many working samples of your ideas have you built Douglas?

Here is ONE place in the world where ppl get the opportunity
to place before the world all their innermost thoughts, feelings,
and amplifier ideas for the general good of mankind,
and also at mankind's mercy, because many samples of robbust
mankind will heap the ****e bucket all over aforesaid published
thoughts, feelings and
design ideas.

This function of bucket emptying is extremely healthy.
It promotes ppl to question their own self-righteousness.
If you don't, then we sure will.
Idealists, or bearers of novel ideas cannot
expect a dreamy un-criticised run after lodging an idea, and so ideas
may have to be PROVEN
to be worth pursuit, or at least rewarding or entertaining to persue, if
not
worth anything.

The way to prove one's ideas work is to build a sample of it and report
results accurately,
knowing that anyone else will get reproducible results if the ideas are
copied elsewhere.

And Schematica is a very easy and informative language to speak
when it comes to assessment of proposed schematics.

To me, there are not a huge number of ways to build an SE amp,
and one way not to build one is to use a PP OPT with some sort of
compensatory
reverse dc flow to oppose the flow in a single tube.

The traditional way is for the OPT to have dc flow and a gapped core,
so the L is like a high inductance air gapped choke
which will sustain a high dc magnetization AND ac magnetization field
strength
evan at 20Hz. With interleaved secondaries thoughout this "choke" coil,
the choke acts as a transformer OK.
I'd never sell an amp made with this idea to anyone.


The next best way is to have DC conveyed to the tube via a choke with a
supply at just above Ea,
or have a CCS supply the anode with a CCS from a supply just above 2 x
Ea,
and then cap couple the anode to a normal easy to obtain PP tranny,
such as made by Hammond engineering to suit a pair of output tubes.
Only the Bac need be accomodated, and no Bdc exists.
Therefore the this PP OPT need not be so large as the SE OPT which
allows for dc flow Bdc.

Patrick Turner.

[David R Brooks]

Andre Jute wrote:
[snip]
Forget it until it happens, then you can fix it. I used to put a mains
rated cap across the mains but no longer do it and don't show it on
new circuits because I know of nobody who found it necessary (and it
is dangerous to get that cap wrong). If and when it happens, you buy a
filter.

The first place I worked (no, I won't confess how long ago still
built valve radios when I was there. In still earlier days, they used
also to do general servicing. A tale from then had it that this "little
old lady" brought in a radio, complaining that it didn't sound right.
They tried everything, but the set was OK, just a cheapie. But she
wouldn't have it, & kept bringing it back.
Finally, they took that AC mains capacitor off, drilled it out, & packed
it with gunpowder before replacing it... Lady takes the set home, plugs
it in: Flash! Bang! And of course the set carries on working! They
didn't see her again...

[Andre Jute]

On Nov 6, 8:49 am, David R Brooks wrote:
Andre Jute wrote:

[snip] Forget it until it happens, then you can fix it. I used to put a mains
rated cap across the mains but no longer do it and don't show it on
new circuits because I know of nobody who found it necessary (and it
is dangerous to get that cap wrong). If and when it happens, you buy a
filter.

The first place I worked (no, I won't confess how long ago still
built valve radios when I was there. In still earlier days, they used
also to do general servicing. A tale from then had it that this "little
old lady" brought in a radio, complaining that it didn't sound right.
They tried everything, but the set was OK, just a cheapie. But she
wouldn't have it, & kept bringing it back.
Finally, they took that AC mains capacitor off, drilled it out, & packed
it with gunpowder before replacing it... Lady takes the set home, plugs
it in: Flash! Bang! And of course the set carries on working! They
didn't see her again...

Little old lady leaning over fence, confides in neighbour, "They're
not much chop as repairmen. They almost exploded my radio. But I
talked to it like child and it plays again. The Lord is all-knowing."

My Trek Navigator L700 "Smover" is fitted up with Shimano's
Cybernexus, computer-controlled automatic internal gears and
suspension. One gear range is called by Shimano L for "leisure" but it
is so low and slow, I call it the "little old lady mode".
http://members.lycos.co.uk/fiultra/B...%20Smover.html

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

[Andre Jute]

You haven't missed anything, Patrick. It looks like Multi-grid is
trying to get John Byrns and and Robert Casey and me to work out a
circuit he dreams of but hasn't built. John warned me but I got
suckered in. I guess hope springs eternal.

"Duggles" is a pun on Multi-grid sucking the rear tit without too fast
a grasp on it.

As for posting a schematic, if Multi-grid doesn't have a netsite and
cannot access ABSE (which is a pain to put something on and
inaccessible to most of us anyway), he can send the schematic to me to
put up on my Discussion page, which I created for precisely that
purpose.

Andre Jute
"Blessed is the man who, having nothing to say, abstains from giving
us wordly evidence of the fact."-- George Elliot


On Nov 6, 8:05 am, Patrick Turner wrote:
Andre Jute wrote:

WTF is this, Cuddles? We've given you multiple chances to tell us what
you're talking about or, better still, show us a schematic but you're
as unbelievably coy as a whore at a sailor's stag night. Just show us
the schematic and let us work it out.

Andre Jute
Patience isn't my best talent

I have been rather busy as usual trying to eek a living from making
exoticly simple and effective amplifiers,
or converting horridly complex piles of yank junk into paradimes of
sonic virtue.

This thread has rapidly become obtuse to the nth degree,
with only an inner circle able to out-imaginatize each other with
wordolgies
that are relevant only for the 10 seconds the few ppl involved have them
in their minds.

I kinda feel I ain't missing out on much by not following it along.

Who was Duggy? Douglas Fartentuber perhaps? He was an outstandingly
inovative European
in the 1950s, invented all this stuff but the yanks copied and patended
his ideas as their own...
But not the brighter ideas about SE though.
Out of sight and out of mind, the Japanese matured their ideas about SE
for about 47 years
until about 1992, when "western" nations suddenly realised there was
some new candy
thay had missed out getting......
I'd never know Japan had ever existed from reading this group.
In the US, consciousness of European existance is all very limited......

Of course the group SHOULD be allowed to show binaries up to say 50kB,
and so .GIFs of schematics would be wonderful rather than having to read
them at
ABSE, where in this country the arsole boffins controlling the Internet
access
make sure you can't see the binaries posts from ABSE. I protested about
it to my ISP
and it was like having a discussion with a dead cat.

What could be done to allow minor binaries r.a.t
?????????????????????????????????????????????????? ??

In the past, one Basset, a mainly horrible man who poses as a dog posted
a .jpg here of his doghouse.

It was not blocked out. He did an earlier image as well...

Patrick Turner.

Snip miles and miles of blahdiddleyah...

[John Byrns]

In article om,
Multi-grid wrote:

Well John I've made it plain that I am not going to hand this out. It
isn't any fun for you, and it is too much work for me. So get with it
if you can. Just remember, I know your belief or understading isn't
required, I've seen it in action.

Maybe, however you have been very stingy with even the most basic
details of the amplifier, all you have said about the amplifier is the
following:

"One can also use heater current. Best SE amp I ever heard was a 50W
monster that had a piddling little output TX. Through a special winding
went the required 25A of heater current for that valve...no intentional
gap needed anymore."

For instance you haven't told us if there is an inductor in the "heater"
circuit, in series with the "special winding", the "heater", and the DC
voltage source supplying the heater? You also haven't told us what
output tube was used in this amplifier?

Since you appear unwilling to supply even these simple details, it's
hard to avoid the conclusion that you are simply shoveling out a bunch
of BS.

You have yet to do anything which deserves my indulgence of your lazy
and closed mind. Behave yourself.
cheers,
Douglas

I'll give you a hint: Think about the power, you've come to an
incorrect conclusion. See if you can find it.

Since you are unwilling to share even the simplest details about your
hypothetical amplifier, I analyzed your circuit under the assumption
that there was no choke in the "heater" circuit, and assuming a
hypothetical output tube. The situation was even worse than I had
assumed with over 70% of the audio power developed by the tube being
lost in the resistance of the "heater".

It's obvious why you don't want to give even the simplest details of
your amplifier, it simply doesn't work without a choke in the
"heater"/transformer "bias" circuit!

Tell us what output tube you used in the amplifier and I will redo my
calculations to suit, and then post them so that my errors will be
obvious to all. The operating point of the tube would also be helpful,
although not absolutely necessary, so I don't have to make an assumption
there.

I'll give you a hint, there are several reasons why we don't see this
idea used in SE amps.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

[John Byrns]

In article om,
Multi-grid wrote:


Well John I've made it plain that I am not going to hand this out. It
isn't any fun for you, and it is too much work for me. So get with it
if you can. Just remember, I know your belief or understading isn't
required, I've seen it in action.

You have yet to do anything which deserves my indulgence of your lazy
and closed mind. Behave yourself.
cheers,
Douglas

I'll give you a hint: Think about the power, you've come to an
incorrect conclusion. See if you can find it.


Since you are not naming the tube used in your amplifier, let's run the
numbers for a popular audiophile tube, the 300B, to see how unworkable
your idea is.

The filament supply for the following calculations is assumed to be a
5.0 volt DC source and no inductor is assumed in the filament circuit.

The 300B filament has the following Characteristics

Vf = 5.0 volts
If = 1.2 amps

This gives the following for the filament resistance.

Rf = 5.0/1.2 = 4.1667 Ohms

For the example I choose the following operating point from the 300B
data sheet.

Va = 350 volts
Vg = -71 volts
Ia = 80 mA
Rl = 2,200 Ohms
Po = 9.6 Watts

With the 1.2 amp filament current and the quiescent anode current of 80
mA, the required turns ratio between the primary and the "special
winding" becomes.

1,200/80 = 15:1

With a filament resistance of 4.1667 Ohms and a turns ratio of 15:1, the
filament resistance reflected to primary side of the transformer becomes.

4.1667 x (15^2) = 937.5 Ohms

Without even connecting a loudspeaker load to the transformer secondary,
the load on the 300B tube is already only half of the desired load
resistance of 2,200 Ohms. The lower than desired load reduces the audio
power the tube can generate, and a large percentage of the audio power
actually generated by the tube is shunted into the tubes heater, with
little left over for the loudspeaker. Other operating conditions give
slightly better results, but the audio load from the filament alone was
still less than the desired load for the tube with all the operating
points I tried.

The results with the hypothetical transmitting tube I tried, which could
easily supply 50 Watts in a normal SE circuit, were essentially
identical to the 300B results presented above.

The above example should illustrate to anyone still following this
discussion that the idea as you have described it simply doesn't work.

The obvious conclusion is that you have something to hide and are
playing some kind game with your claim that this is a workable scheme,
while at the same time refusing to give even the simplest details of the
circuit, like what tube was used.


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

[Iain Churches[_2_]]

"Andre Jute" wrote in message
oups.com...
On Nov 4, 6:52 am, Patrick Turner wrote:

Musicians do not necessarily have any special hearing abilities.

Yes, they do: they have trained perception. They listen consciously.
Non-audiophiles from the general population cannot even hear the
difference between a boombox played through good speakers and a Class
A PP tube amp played through the same speakers. To them it is all
"nice", useless for tests.

This subject of "aural perception" is something close to my heart.
I have been interested for many years to find out what most of us
can and cannot hear. There are dozens of interesting a revealing musical
experiments. It is very easy indeed to fool the untrained ear.

It is, for some reason, fashionable to deride the skill, training and
perception of musicians. It is a pastime in which those without
any musical skills of their own, seem to find a need to participate,
with constant reference to deaf, drug-crazed or otherwise
stupid musicians.

I have worked for many years with professional
classical and jazz musicians of all nationalities.
I am constantly surprised at their levels of perception.

The skill of aural perception is now something that is recognised and
taught at many conservatories of music. It can also have its uses at
a much more elementary level too. There was an English
multi-instrumentalist by the name of Trevor Crozier who used to
visit schools with a large collection of stringed instruments,
from Baroque to modern, to let children hear the sounds
these instruments make, first hand. The students soon began to
differentiate betwen the banjo, the flat-back mandolin and the
dobra.

There are very few musicians of my aquaintance who cannot
differentiate easily between say a Guild and Martin acoustic guitar,
or a Bosendorfer and a Bechstein piano. I know from experience
that few "members of the public" or even audiophiles have this
skill.

It should also be observed that most audiophiles talk big about their
golden ears but in blind tests have poor discrimination, so that you
first require tests to sort out the good listeners. That shocked me;
for a while I wondered if the meterheads weren't right, if vanishing
THD numbers aren't the holy grail after all... But you don't want to
hear about the anguish of an open mind.

At conservatory level, one of the first tests for entry
students is to differentiate between say an alto and a tenor
saxophone playing in the same register. Try. It is not easy.
How many of us here can tell an oboe from a cor Anglais?
Probably not many - and yet we all have ears which receive
the identical information. Some have brains which know how
to process this information, some do not.

Some time ago I was involved in a small-ensemble recording,
of a string quartet with solo clarinet. One the third and last day
of the sessions, the clarinet player was indisposed.
The string players were leaving the following day for a tour,
so it was decided to record the quartet and add the
clarinet a few days later.

Digital technology adds some interesting new tools to
the recording engineer's toolbox. One of these is pitch-shift
without tempo change.

With the artists' permission, we assembled a panel of
some twenty listeners, musicians, studio office staff, the
studio electrician, a taxi driver a window cleaner,
the canteen lady, etc etc.

We then played back the recording, and because there was
no leakage from the post-recorded clarinet onto the strings,
we were able, over the course of some 32 bars, gradually
increase the pitch of the instrument relative to the string
accompaniment. It was interesting to watch the reaction
of the listeners. At the end of twenty four bars, we had
raised the pitch by approx 4%, half a semitone (a quarter
tone for those in the US) The musicians on the panel were
looking decidedly uncomfortable, and writhing in their
seats along the back row. The "general public" were just
enjoying the music, and had noticed nothing.

This experiment was discussed at some length on a closed
group, and the producer of the recording was approached
by several people who wanted to organise their own listening
tests with panels. One of these was the editor or a Scandinavian
hifi magazine. I provided a DAT with time code, containing
two audio segments, one of the quartet, and the other of
the clarinet, which the experimenters could download to their
own DAW to simulate the test which we had carried out.

There is no doubt in my mind that good hearing is not just
being about to hear a sine wave at 18kHz and have this
plotted on an audiogram which you present to your employer
once a yearafter your health check.

Perception, is a skill that requires study and carefull development
over along period of time. Few have it as a natural gift.

Regards to all
Iain

[Iain Churches[_2_]]

"Andre Jute" wrote in message
ups.com...
Dave wrote:

"Andre Jute" wrote in message
ps.com...


The explanation is simple. Loop NFB causes artifacts of ever lower
magnitude but higher order. These high order distortions, even at 60dB
below conscious perception are very, very disturbing, whereas second
harmonic up to three-quarter per cent cannot even be distinguished by
professional musicians. It is a subliminal effect, and of course in
pentode mode it is exaggerated. People look at the total harmonic
distortion but in fact the higher harmonics must be weighted much more
heavily than the second harmonic to account for its extraordinary
subliminal effect, often described as "edgineess" by professional
musicians.


This was the explanation I was looking for. thank you.

Yes. That seems to be a good description of what is going on, and explains
why two similar tubes/valves of the same type but by different makers may
sound different. They usually have the same or very similar THD but the
distortion spectra are sometimes surprisingly different. 2H is exactly an
octave of the fundamental, and so, in "trace" amounts may be regarded as
benign. 3H, 5H, 7H and 9H, even at much lower levels are considerably
more disturbing.

Some years ago, the technical director of Svetlana sent me the findings
of a listening group with whom he had been working. Their task was to
evaluate 6CG7 tubes by different makers, and put them in order of
preference, so that they could be measured and analysed. Although I
was not able to obtain all twelve makes on the list, with some
colleagues, I repeated the experiment.The differences were most interesting.
The interpretation of which is "better" must be left to individual taste,
but in general terms, we ranked the tubes in roughly the same order as
the Svetlana listeners. In case you are wondering, the RCA cleartop
was the best sounding. It also had the lowest odd order harmonics
when measured in a mu follower circuit.

You listen to your speakers, not your amp; I would really advise you,
unless you are married to these insensitive speakers, first to get
good sensitive speakers you can live with forever, then build an amp
to suit them. If you have the space, an inexpensive sensitive speaker
you can build easily is The Impresario on my netsite, url under my
sig. EL84 are particularly sweet in triode but of course pitifully
underpowered for insensitive speakers.


Yes, I know, efficient speakers are on my long-term shopping list. My
current speakers will run nicely on 15W (or even 12W). I have somewhat
limited financial means at my disposal for projects of this sort, but I
do
like the look of the EL34 just because of its' high power output.

What's an acceptable value for distortion?

I have been involved in experiments on which panels of listeners have
been asked to differentiate between two identical amplifiers, one set up to
have 0.05% and the other 0.5% THD. This is a difference of 20dB.
No one, even the professionals on the panel, could tell which was which.

It is a long time since I have read the book, but IIRC Olson states that
listeners could not detect distortion levels up to 1% on a music signal.


Right now I'm running a solid
state amp which is rated at 50W RMS with THD of 0.08%. I guess this
isn't a
reasonable target for a tube amp unless I run multiple parallel UL PP
pairs
per channel...

A while ago, I built a push pull parallel EL34 amp, with two parallel pairs
per channel. It can achieve 0.08% THD at full power.

http://www.kolumbus.fi/iain.churches...em/C50_002.jpg



And NFB up the kazoo. 0.1 per cent is a figure commonly bandied about
but I'm not overly impressed. I know for a fact that people cannot
hear as much as 3/4 per cent second harmonic but can hear that much
odd harmonic very clearly, and many people can hear or are made
uncomfortable by 0.3 per cent odd harmonics. What you want to do is
not to measure at full power but at some lower power where you will
actually use the amp; 1W or 2.83V into 8ohm is a common level with
even semi-sensitive speakers.

Correct. A good PP valve/tube amp can manage 0.03% at 1W
While you should always measure and evaluate an amp in detail,
don't get bogged down in test bench measurements. Don't expect
with a tube amp to be able to apply 75dB of NFB, or achieve a
damping factor in three figures, and a badwidth DC to daylight
as you can in an SS amp. If you want that kind of sound,
buy a Crown:-)

Happy to be of service to a hands-on audiophile. Good luck.

Now we are getting back to RAT as it should be:-)

Iain

[Iain Churches[_2_]]

"Arny Krueger" wrote in message
. ..

"Andre Jute" wrote in message
oups.com...
On Nov 4, 6:52 am, Patrick Turner wrote:

Musicians do not necessarily have any special hearing abilities.

They are also not immune to hearing damage, even occupationally-related.

Neither are car factory workers:-)
Even walking in a busy street can be an aurally daunting experience.

Yes, they do: they have trained perception.

But they are not unique in that regard.

Also, what they listen for is not necessarily the same as what you listen
for when you listen for differences between audio products.

They listen consciously.

That's hardly unique to musicians.

It may not be unique, but they have specific training to help them to
achieve this.

I've done enough listening tests with non-audiophiles and non-musicans to
be careful about putting them all down.

If I could find enough experienced audiophiles -- defined as having
trained their own aural perception -- available on a regular basis, I
would use them instead.

Been there done that. BTW, one good way for audiophiles to train their
perceptions is to spend some time actually listening for differences that
are known to be audible, but perhaps neer the margin of audibility.

But Arny, you have not been there or done that, except perhaps in
a purely amateur capacity. In reply to a question of mine, you stated
that you had neither formal musical education, nor formal training in
recording, so there is no reason to think that your level of aural
perception is any better than Mr/Mrs Average. You might be
embarrassed by the results if you were asked to take some of
the AP tests.

It may interest you to know, and I am pretty sure the US is no different
to the EU in this respect, that when major record companies are looking
out for potential trainees as recording engineers, they place a greater
emphasis on musical ability than on technical expertise. The reason
for this, as explained to me by the technical director of DGG,
is that musical ability is based on a talent, which can be "expanded"
by teaching, but cannot be taught. If you have no sense of pitch,
you have no sense of pitch:-(

So, the major companies seek suitable people for training as Tonmeister,
which is a combination of musical and technical ability. One of the
qualifications even to apply for this course is a level of musical skills,
both theoretical and practical to a professional level.

The technical aspects of recording can be, and are, taught in classroom
and in practical sessions. For this reason, it is very unusual to find a
competent recording engineer who is not also a fairly good musician.

Iain

[Multi-grid]

On Nov 6, 5:28 pm, John Byrns wrote:
In article om,

Multi-grid wrote:
Well John I've made it plain that I am not going to hand this out. It
isn't any fun for you, and it is too much work for me. So get with it
if you can. Just remember, I know your belief or understading isn't
required, I've seen it in action.

Maybe, however you have been very stingy with even the most basic
details of the amplifier, all you have said about the amplifier is the
following:

"One can also use heater current. Best SE amp I ever heard was a 50W
monster that had a piddling little output TX. Through a special winding
went the required 25A of heater current for that valve...no intentional
gap needed anymore."

For instance you haven't told us if there is an inductor in the "heater"
circuit, in series with the "special winding", the "heater", and the DC
voltage source supplying the heater? You also haven't told us what
output tube was used in this amplifier?

Since you appear unwilling to supply even these simple details, it's
hard to avoid the conclusion that you are simply shoveling out a bunch
of BS.

You have yet to do anything which deserves my indulgence of your lazy
and closed mind. Behave yourself.
cheers,
Douglas

I'll give you a hint: Think about the power, you've come to an
incorrect conclusion. See if you can find it.

Since you are unwilling to share even the simplest details about your
hypothetical amplifier, I analyzed your circuit under the assumption
that there was no choke in the "heater" circuit, and assuming a
hypothetical output tube. The situation was even worse than I had
assumed with over 70% of the audio power developed by the tube being
lost in the resistance of the "heater".

It's obvious why you don't want to give even the simplest details of
your amplifier, it simply doesn't work without a choke in the
"heater"/transformer "bias" circuit!

Let me see, you refuse to do any of the work, then 'prove' it can't be
done, and then you suggest I tell you more. What part of "I am not
going to hand this out. It isn't any fun for you, and it is too much
work for me." didn't you understand?

Calling me names isn't going to persuade me to further your
understanding. I think I'll just let it go until you decide it is
worth it to behave yourself.



Tell us what output tube you used in the amplifier and I will redo my
calculations to suit, and then post them so that my errors will be
obvious to all. The operating point of the tube would also be helpful,
although not absolutely necessary, so I don't have to make an assumption
there.

I'll give you a hint, there are several reasons why we don't see this
idea used in SE amps.

None you've seen in your limited travels perhaps. Actually I think a
patent was granted on it, but you can do the searching, I'm sure it
will turn up sooner or later.
cheers,
Douglas

[Andre Jute]

Turner:
Musicians do not necessarily have any special hearing abilities.

Jute:
Yes, they do: they have trained perception. They listen consciously.
Non-audiophiles from the general population cannot even hear the
difference between a boombox played through good speakers and a Class
A PP tube amp played through the same speakers. To them it is all
"nice", useless for tests.

Churches:
This subject of "aural perception" is something close to my heart.
I have been interested for many years to find out what most of us
can and cannot hear. There are dozens of interesting a revealing musical
experiments. It is very easy indeed to fool the untrained ear.

It is, for some reason, fashionable to deride the skill, training and
perception of musicians. It is a pastime in which those without
any musical skills of their own, seem to find a need to participate,
with constant reference to deaf, drug-crazed or otherwise
stupid musicians.

Jute:
I had my assistant call one jazz musician to tell him, "Be compos next
Wednesday so Andre can get sense out of you." He called back to ask if
it would be okay if his parole officer, who read me, came too. I
discovered later the guy is a real uptight middleclass type, complete
with big mortgage, sober car, wife in Little League and 3.8 children.
He dined out for years about sending me up about how he was a
jailbird.

Churches:
I have worked for many years with professional
classical and jazz musicians of all nationalities.
I am constantly surprised at their levels of perception.

The skill of aural perception is now something that is recognised and
taught at many conservatories of music. It can also have its uses at
a much more elementary level too. There was an English
multi-instrumentalist by the name of Trevor Crozier who used to
visit schools with a large collection of stringed instruments,
from Baroque to modern, to let children hear the sounds
these instruments make, first hand. The students soon began to
differentiate betwen the banjo, the flat-back mandolin and the
dobra.

There are very few musicians of my aquaintance who cannot
differentiate easily between say a Guild and Martin acoustic guitar,
or a Bosendorfer and a Bechstein piano. I know from experience
that few "members of the public" or even audiophiles have this
skill.

Jute:
It should also be observed that most audiophiles talk big about their
golden ears but in blind tests have poor discrimination, so that you
first require tests to sort out the good listeners. That shocked me;
for a while I wondered if the meterheads weren't right, if vanishing
THD numbers aren't the holy grail after all... But you don't want to
hear about the anguish of an open mind.

Churches:
At conservatory level, one of the first tests for entry
students is to differentiate between say an alto and a tenor
saxophone playing in the same register. Try. It is not easy.
How many of us here can tell an oboe from a cor Anglais?
Probably not many - and yet we all have ears which receive
the identical information. Some have brains which know how
to process this information, some do not.

Some time ago I was involved in a small-ensemble recording,
of a string quartet with solo clarinet. One the third and last day
of the sessions, the clarinet player was indisposed.
The string players were leaving the following day for a tour,
so it was decided to record the quartet and add the
clarinet a few days later.

Digital technology adds some interesting new tools to
the recording engineer's toolbox. One of these is pitch-shift
without tempo change.

With the artists' permission, we assembled a panel of
some twenty listeners, musicians, studio office staff, the
studio electrician, a taxi driver a window cleaner,
the canteen lady, etc etc.

We then played back the recording, and because there was
no leakage from the post-recorded clarinet onto the strings,
we were able, over the course of some 32 bars, gradually
increase the pitch of the instrument relative to the string
accompaniment. It was interesting to watch the reaction
of the listeners. At the end of twenty four bars, we had
raised the pitch by approx 4%, half a semitone (a quarter
tone for those in the US) The musicians on the panel were
looking decidedly uncomfortable, and writhing in their
seats along the back row. The "general public" were just
enjoying the music, and had noticed nothing.

This is an amazing story. It is much more accurate in these tests to
observe the discomfort of the professionals than to ask them to
intellectualize their reaction, especially at the borders of conscious
perception.

Churches:
This experiment was discussed at some length on a closed
group, and the producer of the recording was approached
by several people who wanted to organise their own listening
tests with panels. One of these was the editor or a Scandinavian
hifi magazine. I provided a DAT with time code, containing
two audio segments, one of the quartet, and the other of
the clarinet, which the experimenters could download to their
own DAW to simulate the test which we had carried out.

There is no doubt in my mind that good hearing is not just
being about to hear a sine wave at 18kHz and have this
plotted on an audiogram which you present to your employer
once a yearafter your health check.

Perception, is a skill that requires study and carefull development
over along period of time. Few have it as a natural gift.

Regards to all
Iain

Andre Jute
Perception is a skill that requires study and careful development
over along period of time. Few have it as a natural gift. -- Iain
Churches

[John Byrns]

In article . com,
Multi-grid wrote:

On Nov 6, 5:28 pm, John Byrns wrote:
In article om,

It's obvious why you don't want to give even the simplest details of
your amplifier, it simply doesn't work without a choke in the
"heater"/transformer "bias" circuit!

Let me see, you refuse to do any of the work, then 'prove' it can't be
done, and then you suggest I tell you more.

You obviously didn't read my other post where I gave a mathematical
derivation demonstrating why it doesn't work

What part of "I am not
going to hand this out.

I don't think that is a complete sentence.

It isn't any fun for you, and it is too much
work for me." didn't you understand?

Of course it's fun for me, I wouldn't be playing along with your game if
I wasn't having fun toying with you. I understood your position in this
discussion a dozen or more posts ago, and realized that there would be
no information forthcoming from you.

Tell us what output tube you used in the amplifier and I will redo my
calculations to suit, and then post them so that my errors will be
obvious to all.

I didn't realize that typing a tube type number which is probably eight
or fewer characters was so much work, especially for someone who can so
easily type paragraphs of utter nonsense.

I'll give you a hint, there are several reasons why we don't see this
idea used in SE amps.

None you've seen in your limited travels perhaps.

As I said I have seen several reasons in my travels, your skull is
simply to thick for them penetrate, and if they did you are obviously
too lazy to make any effort to understand them.

Actually I think a
patent was granted on it, but you can do the searching, I'm sure it
will turn up sooner or later.

I wouldn't be at all surprised if there was a patent on it, a patent in
no way implies that an "invention" is practical or useful. Why would I
want to search for the patent, assuming it exists?


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

[Andre Jute]

Jute:
The explanation is simple. Loop NFB causes artifacts of ever lower
magnitude but higher order. These high order distortions, even at 60dB
below conscious perception are very, very disturbing, whereas second
harmonic up to three-quarter per cent cannot even be distinguished by
professional musicians. It is a subliminal effect, and of course in
pentode mode it is exaggerated. People look at the total harmonic
distortion but in fact the higher harmonics must be weighted much more
heavily than the second harmonic to account for its extraordinary
subliminal effect, often described as "edgineess" by professional
musicians.

Dave:
This was the explanation I was looking for. thank you.

Churches:
Yes. That seems to be a good description of what is going on, and explains
why two similar tubes/valves of the same type but by different makers may
sound different. They usually have the same or very similar THD but the
distortion spectra are sometimes surprisingly different. 2H is exactly an
octave of the fundamental, and so, in "trace" amounts may be regarded as
benign. 3H, 5H, 7H and 9H, even at much lower levels are considerably
more disturbing.

Lynn Olson published an article in Glass Audio about how topologies
can make different spectra too, from which you could read how the
different tubes performed on the same topology. Even while he was
working on his article, I made some vastly less ambitious test on 6SN7
and 6SNL7 tubes, the small-signal tubes I like best next to the 417A,
and published the results on the Joenet where even guys many decades
in tubes were surprised by the results; possibly some of them didn't
believe me until Lynn published his results which matched mine pretty
closely. Lynn's stunning article is somewhere on his netsite.

Also, you should look into topologies with THD spectra in tables (Lynn
shows colored ribbon-graphs) that Steve Bench published; for years I
designed my voltage gain and driver stages with Steve's tables
constantly at my elbow.

Churches:
Some years ago, the technical director of Svetlana sent me the findings
of a listening group with whom he had been working. Their task was to
evaluate 6CG7 tubes by different makers, and put them in order of
preference, so that they could be measured and analysed. Although I
was not able to obtain all twelve makes on the list, with some
colleagues, I repeated the experiment.The differences were most interesting.
The interpretation of which is "better" must be left to individual taste,
but in general terms, we ranked the tubes in roughly the same order as
the Svetlana listeners. In case you are wondering, the RCA cleartop
was the best sounding. It also had the lowest odd order harmonics
when measured in a mu follower circuit.

Jute:
You listen to your speakers, not your amp; I would really advise you,
unless you are married to these insensitive speakers, first to get
good sensitive speakers you can live with forever, then build an amp
to suit them. If you have the space, an inexpensive sensitive speaker
you can build easily is The Impresario on my netsite, url under my
sig. EL84 are particularly sweet in triode but of course pitifully
underpowered for insensitive speakers.

Dave:
Yes, I know, efficient speakers are on my long-term shopping list. My
current speakers will run nicely on 15W (or even 12W). I have somewhat
limited financial means at my disposal for projects of this sort, but I
do
like the look of the EL34 just because of its' high power output.


Churches:
I have been involved in experiments on which panels of listeners have
been asked to differentiate between two identical amplifiers, one set up to
have 0.05% and the other 0.5% THD. This is a difference of 20dB.
No one, even the professionals on the panel, could tell which was which.

Iain then goes on to say:
It is a long time since I have read the book, but IIRC Olson states that
listeners could not detect distortion levels up to 1% on a music signal.

Olson worked with experienced listeners, broadcast types. After two
generations more in which hi-fi was a commonplace in a very large
proportion of homes, I think more experienced listeners should be
found in the general population, which is why I set my bar at 0.75 per
cent for second harmonic and quite bit lower for higher harmonics.

Dave:
Right now I'm running a solid
state amp which is rated at 50W RMS with THD of 0.08%. I guess this
isn't a
reasonable target for a tube amp unless I run multiple parallel UL PP
pairs
per channel...

Churches:
A while ago, I built a push pull parallel EL34 amp, with two parallel pairs
per channel. It can achieve 0.08% THD at full power.

http://www.kolumbus.fi/iain.churches...em/C50_002.jpg

Jute:
And NFB up the kazoo. 0.1 per cent is a figure commonly bandied about
but I'm not overly impressed. I know for a fact that people cannot
hear as much as 3/4 per cent second harmonic but can hear that much
odd harmonic very clearly, and many people can hear or are made
uncomfortable by 0.3 per cent odd harmonics. What you want to do is
not to measure at full power but at some lower power where you will
actually use the amp; 1W or 2.83V into 8ohm is a common level with
even semi-sensitive speakers.

Churches:
Correct. A good PP valve/tube amp can manage 0.03% at 1W

Irrelevantly, of course...

Churches:
While you should always measure and evaluate an amp in detail,
don't get bogged down in test bench measurements. Don't expect
with a tube amp to be able to apply 75dB of NFB, or achieve a
damping factor in three figures, and a badwidth DC to daylight
as you can in an SS amp. If you want that kind of sound,
buy a Crown:-)

Jute:
Happy to be of service to a hands-on audiophile. Good luck.

Churches:
Now we are getting back to RAT as it should be:-)

You gotta take the rough with the smooth, pal, and never let on that
it disturbs your equilibrium or the Magnequest Scum and other sharks
will perceive it as a weakness start camping out permanently on RAT.

Iain

Andre Jute
"I was at a board meeting for the LA Chapter of the Audio Engineering
Society last night on XM Satellite radio audio and data transmission.
Sadly, we missed you there, and at the SMPTE and Acoustical Society
recent meetings as well. Everyone was asking, 'Where is that wonderful
Andre Jute? The world just doesn't rotate without him...'" -- John
Mayberry, Emmaco

[Andre Jute]

On Nov 6, 11:02 pm, Multi-grid wrote:
On Nov 6, 5:28 pm, John Byrns wrote:



In article om,

Multi-grid wrote:
Well John I've made it plain that I am not going to hand this out. It
isn't any fun for you, and it is too much work for me. So get with it
if you can. Just remember, I know your belief or understading isn't
required, I've seen it in action.

Maybe, however you have been very stingy with even the most basic
details of the amplifier, all you have said about the amplifier is the
following:

"One can also use heater current. Best SE amp I ever heard was a 50W
monster that had a piddling little output TX. Through a special winding
went the required 25A of heater current for that valve...no intentional
gap needed anymore."

For instance you haven't told us if there is an inductor in the "heater"
circuit, in series with the "special winding", the "heater", and the DC
voltage source supplying the heater? You also haven't told us what
output tube was used in this amplifier?

Since you appear unwilling to supply even these simple details, it's
hard to avoid the conclusion that you are simply shoveling out a bunch
of BS.

You have yet to do anything which deserves my indulgence of your lazy
and closed mind. Behave yourself.
cheers,
Douglas

I'll give you a hint: Think about the power, you've come to an
incorrect conclusion. See if you can find it.

Since you are unwilling to share even the simplest details about your
hypothetical amplifier, I analyzed your circuit under the assumption
that there was no choke in the "heater" circuit, and assuming a
hypothetical output tube. The situation was even worse than I had
assumed with over 70% of the audio power developed by the tube being
lost in the resistance of the "heater".

It's obvious why you don't want to give even the simplest details of
your amplifier, it simply doesn't work without a choke in the
"heater"/transformer "bias" circuit!

Let me see, you refuse to do any of the work, then 'prove' it can't be
done, and then you suggest I tell you more. What part of "I am not
going to hand this out. It isn't any fun for you, and it is too much
work for me." didn't you understand?

Calling me names isn't going to persuade me to further your
understanding. I think I'll just let it go until you decide it is
worth it to behave yourself.



Tell us what output tube you used in the amplifier and I will redo my
calculations to suit, and then post them so that my errors will be
obvious to all. The operating point of the tube would also be helpful,
although not absolutely necessary, so I don't have to make an assumption
there.

I'll give you a hint, there are several reasons why we don't see this
idea used in SE amps.

None you've seen in your limited travels perhaps. Actually I think a
patent was granted on it, but you can do the searching, I'm sure it
will turn up sooner or later.
cheers,
Douglas

Hey, Dougles, I don't suppose you go into pubs much, go to games,
anywhere you might meet strangers. Otherwise that impertinent lip
would long since have been knocked off you. Where do you come from to
speak to a guy like John Byrns, who was working with HV tubes before
you were born, with so little respect? You're an embarrassment to the
manners your mother taught you.

Andre Jute

[Multi-grid]

On Nov 7, 2:18 am, Andre Jute wrote:
On Nov 6, 11:02 pm, Multi-grid wrote:





On Nov 6, 5:28 pm, John Byrns wrote:

In article om,

Multi-grid wrote:
Well John I've made it plain that I am not going to hand this out. It
isn't any fun for you, and it is too much work for me. So get with it
if you can. Just remember, I know your belief or understading isn't
required, I've seen it in action.

Maybe, however you have been very stingy with even the most basic
details of the amplifier, all you have said about the amplifier is the
following:

"One can also use heater current. Best SE amp I ever heard was a 50W
monster that had a piddling little output TX. Through a special winding
went the required 25A of heater current for that valve...no intentional
gap needed anymore."

For instance you haven't told us if there is an inductor in the "heater"
circuit, in series with the "special winding", the "heater", and the DC
voltage source supplying the heater? You also haven't told us what
output tube was used in this amplifier?

Since you appear unwilling to supply even these simple details, it's
hard to avoid the conclusion that you are simply shoveling out a bunch
of BS.

You have yet to do anything which deserves my indulgence of your lazy
and closed mind. Behave yourself.
cheers,
Douglas

I'll give you a hint: Think about the power, you've come to an
incorrect conclusion. See if you can find it.

Since you are unwilling to share even the simplest details about your
hypothetical amplifier, I analyzed your circuit under the assumption
that there was no choke in the "heater" circuit, and assuming a
hypothetical output tube. The situation was even worse than I had
assumed with over 70% of the audio power developed by the tube being
lost in the resistance of the "heater".

It's obvious why you don't want to give even the simplest details of
your amplifier, it simply doesn't work without a choke in the
"heater"/transformer "bias" circuit!

Let me see, you refuse to do any of the work, then 'prove' it can't be
done, and then you suggest I tell you more. What part of "I am not
going to hand this out. It isn't any fun for you, and it is too much
work for me." didn't you understand?

Calling me names isn't going to persuade me to further your
understanding. I think I'll just let it go until you decide it is
worth it to behave yourself.

Tell us what output tube you used in the amplifier and I will redo my
calculations to suit, and then post them so that my errors will be
obvious to all. The operating point of the tube would also be helpful,
although not absolutely necessary, so I don't have to make an assumption
there.

I'll give you a hint, there are several reasons why we don't see this
idea used in SE amps.

None you've seen in your limited travels perhaps. Actually I think a
patent was granted on it, but you can do the searching, I'm sure it
will turn up sooner or later.
cheers,
Douglas

Hey, Dougles, I don't suppose you go into pubs much, go to games,
anywhere you might meet strangers. Otherwise that impertinent lip
would long since have been knocked off you. Where do you come from to
speak to a guy like John Byrns, who was working with HV tubes before
you were born, with so little respect? You're an embarrassment to the
manners your mother taught you.

Andre Jute- Hide quoted text -

- Show quoted text -

I showed John exactly the respect he deserved. I'd extend him the same
courtesy if he were sitting in front of me; you to for that matter.
Get off your ass and do something constructive, and quite whining
about not beeing bottle-fed and burped.

As to the rest, you're free to fabricate, speculate, and bluster all
you want...
cheers,
Douglas

[sparky]

On Nov 6, 7:05 pm, John Byrns wrote:
In article . com,

Multi-grid wrote:
On Nov 6, 5:28 pm, John Byrns wrote:
In article om,

It's obvious why you don't want to give even the simplest details of
your amplifier, it simply doesn't work without a choke in the
"heater"/transformer "bias" circuit!

Let me see, you refuse to do any of the work, then 'prove' it can't be
done, and then you suggest I tell you more.

You obviously didn't read my other post where I gave a mathematical
derivation demonstrating why it doesn't work

What part of "I am not
going to hand this out.

I don't think that is a complete sentence.

It isn't any fun for you, and it is too much
work for me." didn't you understand?

Of course it's fun for me, I wouldn't be playing along with your game if
I wasn't having fun toying with you. I understood your position in this
discussion a dozen or more posts ago, and realized that there would be
no information forthcoming from you.

Tell us what output tube you used in the amplifier and I will redo my
calculations to suit, and then post them so that my errors will be
obvious to all.

I didn't realize that typing a tube type number which is probably eight
or fewer characters was so much work, especially for someone who can so
easily type paragraphs of utter nonsense.

I'll give you a hint, there are several reasons why we don't see this
idea used in SE amps.

None you've seen in your limited travels perhaps.

As I said I have seen several reasons in my travels, your skull is
simply to thick for them penetrate, and if they did you are obviously
too lazy to make any effort to understand them.

Actually I think a
patent was granted on it, but you can do the searching, I'm sure it
will turn up sooner or later.

I wouldn't be at all surprised if there was a patent on it, a patent in
no way implies that an "invention" is practical or useful. Why would I
want to search for the patent, assuming it exists?

Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

It is very hard to reason with a fanatic who has limited knowledge of
the subject.

[Iain Churches[_2_]]

"Andre Jute" wrote in message
ups.com...

:
Olson worked with experienced listeners, broadcast types. After two
generations more in which hi-fi was a commonplace in a very large
proportion of homes, I think more experienced listeners should be
found in the general population, which is why I set my bar at 0.75 per
cent for second harmonic and quite bit lower for higher harmonics.


I agree. But there seems to be a general feeling that levels of expectation
have fallen considerably, (and with it the standard reference by which we
all make our evalöuations) with the advent of radio transmitting compressed
audio from already chronically compressed CD's. Plus of course -mp3.
Music has become like wallpaper. Something ubiquitous which people
expect but do not really pay much attention to.

Take a look at the signal envelope of a typical pop-chart CD. In many
cases you will find severe compression and clipping. I know from
my close connections with record labels that CD returns for
technical reasons are very low indeed. I have asked the children
of friends who buy this kind of music whether or not they find this clipping
disturbing. Usually the reply is, "it sounds good and loud in the car"

Iain

[Patrick Turner]

Andre Jute wrote:

Turner:
Musicians do not necessarily have any special hearing abilities.

Jute:
Yes, they do: they have trained perception. They listen consciously.
Non-audiophiles from the general population cannot even hear the
difference between a boombox played through good speakers and a Class
A PP tube amp played through the same speakers. To them it is all
"nice", useless for tests.

Churches:
This subject of "aural perception" is something close to my heart.
I have been interested for many years to find out what most of us
can and cannot hear. There are dozens of interesting a revealing musical
experiments. It is very easy indeed to fool the untrained ear.

It is, for some reason, fashionable to deride the skill, training and
perception of musicians. It is a pastime in which those without
any musical skills of their own, seem to find a need to participate,
with constant reference to deaf, drug-crazed or otherwise
stupid musicians.

Jute:
I had my assistant call one jazz musician to tell him, "Be compos next
Wednesday so Andre can get sense out of you." He called back to ask if
it would be okay if his parole officer, who read me, came too. I
discovered later the guy is a real uptight middleclass type, complete
with big mortgage, sober car, wife in Little League and 3.8 children.
He dined out for years about sending me up about how he was a
jailbird.

Churches:
I have worked for many years with professional
classical and jazz musicians of all nationalities.
I am constantly surprised at their levels of perception.

The skill of aural perception is now something that is recognised and
taught at many conservatories of music. It can also have its uses at
a much more elementary level too. There was an English
multi-instrumentalist by the name of Trevor Crozier who used to
visit schools with a large collection of stringed instruments,
from Baroque to modern, to let children hear the sounds
these instruments make, first hand. The students soon began to
differentiate betwen the banjo, the flat-back mandolin and the
dobra.

There are very few musicians of my aquaintance who cannot
differentiate easily between say a Guild and Martin acoustic guitar,
or a Bosendorfer and a Bechstein piano. I know from experience
that few "members of the public" or even audiophiles have this
skill.

Jute:
It should also be observed that most audiophiles talk big about their
golden ears but in blind tests have poor discrimination, so that you
first require tests to sort out the good listeners. That shocked me;
for a while I wondered if the meterheads weren't right, if vanishing
THD numbers aren't the holy grail after all... But you don't want to
hear about the anguish of an open mind.

Churches:
At conservatory level, one of the first tests for entry
students is to differentiate between say an alto and a tenor
saxophone playing in the same register. Try. It is not easy.
How many of us here can tell an oboe from a cor Anglais?
Probably not many - and yet we all have ears which receive
the identical information. Some have brains which know how
to process this information, some do not.

Some time ago I was involved in a small-ensemble recording,
of a string quartet with solo clarinet. One the third and last day
of the sessions, the clarinet player was indisposed.
The string players were leaving the following day for a tour,
so it was decided to record the quartet and add the
clarinet a few days later.

Digital technology adds some interesting new tools to
the recording engineer's toolbox. One of these is pitch-shift
without tempo change.

With the artists' permission, we assembled a panel of
some twenty listeners, musicians, studio office staff, the
studio electrician, a taxi driver a window cleaner,
the canteen lady, etc etc.

We then played back the recording, and because there was
no leakage from the post-recorded clarinet onto the strings,
we were able, over the course of some 32 bars, gradually
increase the pitch of the instrument relative to the string
accompaniment. It was interesting to watch the reaction
of the listeners. At the end of twenty four bars, we had
raised the pitch by approx 4%, half a semitone (a quarter
tone for those in the US) The musicians on the panel were
looking decidedly uncomfortable, and writhing in their
seats along the back row. The "general public" were just
enjoying the music, and had noticed nothing.

This is an amazing story. It is much more accurate in these tests to
observe the discomfort of the professionals than to ask them to
intellectualize their reaction, especially at the borders of conscious
perception.

Churches:
This experiment was discussed at some length on a closed
group, and the producer of the recording was approached
by several people who wanted to organise their own listening
tests with panels. One of these was the editor or a Scandinavian
hifi magazine. I provided a DAT with time code, containing
two audio segments, one of the quartet, and the other of
the clarinet, which the experimenters could download to their
own DAW to simulate the test which we had carried out.

There is no doubt in my mind that good hearing is not just
being about to hear a sine wave at 18kHz and have this
plotted on an audiogram which you present to your employer
once a yearafter your health check.

Perception, is a skill that requires study and carefull development
over along period of time. Few have it as a natural gift.

Regards to all
Iain

Andre Jute
Perception is a skill that requires study and careful development
over along period of time. Few have it as a natural gift. -- Iain
Churches

A long time ago in the 1970s occasionally ppl would hand me a smoking
joint at a party.

I'd take a draw, and boy, did I ever become ****ing perceptive!!!!
Everything seemed so darned funny, and Dylan seemed really sensible!

I'd ride home on the motorcycle still high, but real slow, seeing the
dangers that lurked everywhere.
I'd be able to hear each tooth in the gearbox, each and every tappet,
and pistons slapping
cyinder walls.
Sometimes I'd have a shiela on the back, tits pressing into me, and we's
stop
maybe at nice park by Sydney's Harbour at 1am and do it right there.

At the party I understood words and music and women much better.

Men usually find all three taken separately a very large challenge.
Taken together, its almost impossible....

But at chess or doing accounts the next day I was bleeding hopeless;
so there was a price to pay for perception enhancement at parties,
notwithstanding the slight shagger's back syndrome.

One either has or has not got natural talent to handle music or
rattlingly fast
conversations in horrid venues.
And who can teach us about shielas?????????

Its like art. All the real greats didn't need too much teaching;
maybe where the paint was kept, and how to be technical without paying
anything, and then their
abilities and masterpeices just flowed out...

Youse 'av got it, or youse ain't got it.

Now I have a cyclist's back, cheaper to obtain than a shagger's back.

And many women don't have a clue about music, sex, chess, triodes, or
bicycles.

Patrick Turner.

[Andre Jute]

On Nov 7, 7:34 am, "Iain Churches" wrote:
"Andre Jute" wrote in message

ups.com...

:

Olson worked with experienced listeners, broadcast types. After two
generations more in which hi-fi was a commonplace in a very large
proportion of homes, I think more experienced listeners should be
found in the general population, which is why I set my bar at 0.75 per
cent for second harmonic and quite bit lower for higher harmonics.

I agree. But there seems to be a general feeling that levels of expectation
have fallen considerably, (and with it the standard reference by which we
all make our evalöuations) with the advent of radio transmitting compressed
audio from already chronically compressed CD's. Plus of course -mp3.
Music has become like wallpaper. Something ubiquitous which people
expect but do not really pay much attention to.

Take a look at the signal envelope of a typical pop-chart CD. In many
cases you will find severe compression and clipping. I know from
my close connections with record labels that CD returns for
technical reasons are very low indeed. I have asked the children
of friends who buy this kind of music whether or not they find this clipping
disturbing. Usually the reply is, "it sounds good and loud in the car"

Iain

Uh-huh. I wondered if I should mention what you describe:
" levels of expectation have fallen considerably, (and with it the
standard reference by which we all make our evalöuations)" but decided
not to complicate what I wrote with qualifications (no doubt Trevor
Wilson will next accuse me of *lying*!). It seems to me that somewhere
around or perhaps after 1990 there was a turning point at which
quantity replaced quality (in a strictly technical sense: the quality
of the content of of the best classical recordings, which is what I
know about, in the 80s and 90s was extraordinary). It coincided with
MP3, miniaturized personal players and so on. But there were still
audiophiles among the higheer socioeconomic groups. The killer --
where I think futureaudio-historians will point the finger -- was the
rise home cinema, which took the attention and disposable income
previously spent on music-audio and on music, and took it in precisely
the key market niche. That also accounts for why the hi-fi industry so
easily sashayed itself into the home video industry: they were dealing
with the same customers.

However, none of this subverts my main thesis, that the people (guys
actually -- Harvey Rosenberg pointed out that audio xstacists are
almost invariably men) now in the age and income bracket to be serious
audiophiles grew up in that period when expectations rose. I would
expect a serious audio group (the Melbourne Club to which Patrick
refers and of which my friend Peter Allen is a leading member is a
good example) to have reached and maintained a much higher level of
discrimination than Olson found among professional half a century and
more ago.

You know that joke Patrick tells against Halcro, about the time the
Hong Kong Audio Club tested one? To a lateral thinker it is instant
proof of not only this contention of mine but another more
controversial matter on which you and I also agree, that the mix of
artifacts in THD is as important as its level. The HK club said, "Ah
so! Halcro sound like 300B, only louder." I know I said the glib thing
about not offending pretty PR dollies the other day, but on second
thoughts I have concluded they didn't make a mistake, nor were they
being overly polite. First, I'm willing to bet that these high-level
amateurs have trained their perception and discrimination to a very
high level. Second, they were reacting to the fact that the Halcro
drives the higher artifacts so far below perception that the residual
second harmonic, minuscule as it may be, again comes to dominate
perception, and clearly at more than a subliminal level to make that
sort of apparently simplistic but in fact deeply profound judgement. I
don't imagine Halcro will give a tubie presumed to be hostile to
silicon (I'm not but you can't buck street myth) access to their
detailed spectrum analysis, but I wouldn't expect anyone who knows
what he's talking about to bet large sums of money that I am wrong.

Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

[Iain Churches[_2_]]

"Andre Jute" wrote in message
oups.com...

Iain wrote:
We then played back the recording, and because there was
no leakage from the post-recorded clarinet onto the strings,
we were able, over the course of some 32 bars, gradually
increase the pitch of the instrument relative to the string
accompaniment. It was interesting to watch the reaction
of the listeners. At the end of twenty four bars, we had
raised the pitch by approx 4%, half a semitone (a quarter
tone for those in the US) The musicians on the panel were
looking decidedly uncomfortable, and writhing in their
seats along the back row. The "general public" were just
enjoying the music, and had noticed nothing.

This is an amazing story. It is much more accurate in these tests to
observe the discomfort of the professionals than to ask them to
intellectualize their reaction, especially at the borders of conscious
perception.


In the tests in which I have helped to organise, we have
specifically asked people to listen but *not* to speak. Each person
will be asked to fill in a questionnaire and also have an opportunity
to state his/her findings verbally at the end.

Also, in comparison tests, the word *better* is not used. One
is interested to know if, for example, two instruments or two
amplifiers sound *different* The opinion as to which one is
better (which in the case of an amplifier does not necessarily
mean more accurate) varies widely from person to person.


Iain

[robert casey]

Arny Krueger wrote:



I've definately worked with classical musicans with serious ear damage.
While they generally have good acuity when it comes to tone and timing,
there's a lot that goes wrong in audio that is independent of that.



While not a classical musician, one of the members of the band "The Who"
had warned people that they should avoid cranking their amps up high
while drunk as a skunk, or else they'll blow their ears out like he did.

So he of "the Who" would not be one "Who is useful for listening tests?"
:-)
(ducking, running for cover)
:-)

[Patrick Turner]

Andre Jute wrote:

On Nov 7, 7:34 am, "Iain Churches" wrote:
"Andre Jute" wrote in message

ups.com...

:

Olson worked with experienced listeners, broadcast types. After two
generations more in which hi-fi was a commonplace in a very large
proportion of homes, I think more experienced listeners should be
found in the general population, which is why I set my bar at 0.75 per
cent for second harmonic and quite bit lower for higher harmonics.

I agree. But there seems to be a general feeling that levels of expectation
have fallen considerably, (and with it the standard reference by which we
all make our evalöuations) with the advent of radio transmitting compressed
audio from already chronically compressed CD's. Plus of course -mp3.
Music has become like wallpaper. Something ubiquitous which people
expect but do not really pay much attention to.

Take a look at the signal envelope of a typical pop-chart CD. In many
cases you will find severe compression and clipping. I know from
my close connections with record labels that CD returns for
technical reasons are very low indeed. I have asked the children
of friends who buy this kind of music whether or not they find this clipping
disturbing. Usually the reply is, "it sounds good and loud in the car"

Iain

Uh-huh. I wondered if I should mention what you describe:
" levels of expectation have fallen considerably, (and with it the
standard reference by which we all make our evalöuations)" but decided
not to complicate what I wrote with qualifications (no doubt Trevor
Wilson will next accuse me of *lying*!).


Shock, Horror, will someone tell you if you lied? how awful....


It seems to me that somewhere
around or perhaps after 1990 there was a turning point at which
quantity replaced quality (in a strictly technical sense: the quality
of the content of of the best classical recordings, which is what I
know about, in the 80s and 90s was extraordinary).

The rot started with the CD I thought.....

And then amount of classical recording nose dived.

there was all this stuff thet existed on mastertapes which could be
recycled
and re-sold again but on CD....

How many recordings of Vivaldi's Four Seasons does the world really
need?

It coincided with
MP3, miniaturized personal players and so on. But there were still
audiophiles among the higheer socioeconomic groups. The killer --
where I think futureaudio-historians will point the finger -- was the
rise home cinema, which took the attention and disposable income
previously spent on music-audio and on music, and took it in precisely
the key market niche. That also accounts for why the hi-fi industry so
easily sashayed itself into the home video industry: they were dealing
with the same customers.

Once baby boomers needed music to enliven dull nights with lovers.
So they all bought "sound systems" with a TT and a cassette player.

They got married and had a couple of kids and then came the VCR,
mainly propelled by making it easy and non embarrassing to watch porno
at home.

Wives could happily watch Gone With the Wind yet again without TV adds.

The major hi-fi shops all turned to HT when the hardware all became
affordable.

Fact is most people really like lounging infront of a picture, and once
they do,
they don't focus on the sound which is really horrible in many
film soundtracks.

Listening to music is akin to reading a book; one needs to use one's
imagination.

"What does this mean?" is asked when listening to Liszt.
( http://www.naxos.com/composerinfo/bi...collection.htm )

One wonder's what the hell went through Liszt's mind when he wrote his
notes...

Being home listening to opera without subtitles can be boring...

Anyway, after awhile a lotta ppl got sick and tired of musical evenings
even with a book to read and were easily seduced by mainly Hollywood
crap on TV and then HT.



However, none of this subverts my main thesis, that the people (guys
actually -- Harvey Rosenberg pointed out that audio xstacists are
almost invariably men) now in the age and income bracket to be serious
audiophiles grew up in that period when expectations rose.

Yeah, there were the 2% of folks who always couldn't accept television
which they equated to a crude form ot home invasion by philistine
troglodytes.

I found TV watching to be unsatidfying, and a waste of precious time,
and have not owned any working visual home media for the last 15 years.
I'm too busy doing my life than watching other do theirs.
If I want to see a film I go out to see it.



I would
expect a serious audio group (the Melbourne Club to which Patrick
refers and of which my friend Peter Allen is a leading member is a
good example) to have reached and maintained a much higher level of
discrimination than Olson found among professional half a century and
more ago.

But someone once managed to re-record a CD into MP3, then back onto a CD
and play what was left to a gathering at the MAC, and nobody said
anything was wrong
with the recording, until they were told they'd been all tricked......

I keep an open mind about who has good ears and who hasn't.



You know that joke Patrick tells against Halcro, about the time the
Hong Kong Audio Club tested one? To a lateral thinker it is instant
proof of not only this contention of mine but another more
controversial matter on which you and I also agree, that the mix of
artifacts in THD is as important as its level. The HK club said, "Ah
so! Halcro sound like 300B, only louder."

Hmm, that's not quite how I told it, I said it went like this...

"Ah, Halcro, it like 300B, but go louder."

( My source of this quotation are as reliable as possible of course, but
as theings get quoted along, the
story starts to change. The New Testament is a fine example of story
change, and embellishments.)

This doesn't mean it sounds like a 300B, or as good as a 300B.

Its like a 300B because it amplifies a signal for a speaker. And it does
manage to go louder if you wish.

For the lads in HK, the SE 300B probably had become a gold standard.
And introducing some expensive new fangled thingemebob amoung
some ultra conservative old chinese *******s wasn't ever going to easily
change any minds.

I have no idea what else was said about the Halcro amplifiers.

In other words, the HK mob could have said, "Well so what? what's the
big deal eh."


I know I said the glib thing
about not offending pretty PR dollies the other day, but on second
thoughts I have concluded they didn't make a mistake, nor were they
being overly polite. First, I'm willing to bet that these high-level
amateurs have trained their perception and discrimination to a very
high level. Second, they were reacting to the fact that the Halcro
drives the higher artifacts so far below perception that the residual
second harmonic, minuscule as it may be, again comes to dominate
perception, and clearly at more than a subliminal level to make that
sort of apparently simplistic but in fact deeply profound judgement.

It may be easy to say all that but ANY artifact in very many SS amps at
5 watts
is often well below the noise floor of the amp.

Halcro amps generate very little 2H in any level of signal at any F.

People used to say this about amps which broke through the THD = 0.01%
barrier 40 years ago. They were all PP amps.
So when you add another two zeros after the decimal point, it becomes
definately pointless to me at least to use technical arguments about THD
and IMD
and percieved sound quality, because the artifacts are so far below
audibility.


I don't imagine Halcro will give a tubie presumed to be hostile to
silicon (I'm not but you can't buck street myth) access to their
detailed spectrum analysis, but I wouldn't expect anyone who knows
what he's talking about to bet large sums of money that I am wrong.

I am not a betting man.

Patrick Turner.



Andre Jute
Visit Jute on Amps at http://members.lycos.co.uk/fiultra/
"wonderfully well written and reasoned information
for the tube audio constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site
containing vital gems of wisdom"
Stuart Perry Hi-Fi News & Record Review

[RdM]

Patrick Turner writes, inter alia, in
. au:

How many recordings of Vivaldi's Four Seasons does the world really
need?

Oh, well over 400, I should think ...
http://svalander.se/vivaldi.htm

In June 2002 I sent him details of one I had that he hadn't; not even on his
wanted list, so probably not known to him; Quattro Stagioni by the
Kammerensemble Cologne, on the Swiss Kutlu label; the lead violinist played a
1724 Stradivarius; I bought the CD after the concert at the church they played
in here; I miss it very much, it having been left at a friends place which was
like a railway station with regular weekly music nights, and vanished ...

I'd very much like a copy again, if anybody ever sees one:
http://i17.tinypic.com/6ypj5zm.jpg

And perhaps some of the recording quality had to do with the equipment used:
http://i11.tinypic.com/8evj28x.jpg (trimmed, much reduced quality of scan!)
(I had thought I might see if I could sneak a 40kb jpg into a text attachment
to the end of this message, re recent discussions, but nah, can't be bothered)

AJ may NB the Stax SR-Lambda Pro used for monitoring.
Not sure if the comment on "transformerless" will win PT's heart, though!
[No "tubes", either!]
--
Ross Matheson
(in nz, not zz...)

[Andre Jute]

On Nov 8, 6:32 am, Patrick Turner wrote:
Andre Jute wrote:
,,,but decided
not to complicate what I wrote with qualifications (no doubt Trevor
Wilson will next accuse me of *lying*!).

Shock, Horror, will someone tell you if you lied? how awful....

I don't mind if I'm wrong on some statement I made being corrected,
preferably politely of course. But Wilson accuses people of lying if
they don't include his fave Blow Jobs for Transvestites when they talk
about tubes; I just don't see how such an omission is a lie. If I want
to talk about BJTs, I can go to the alt.perverts.ss.gruppenfuhrer
newsgroup. But jokes aside, if we once open the door to a single mad
obsessive like Trevor Wilson, soon we'll have one-string ramkiekie
players around here demanding to know why they aren't mentioned every
time we mention a favourite recording of say, a Bach Cantata. The
Wilson Road runs from madness to madness.

And Cantata 199 to every cyclist: "My heart pumps a whole lotta
blood", freely translated (very) from the Cherman "Mein Herze swimt im
Blut."

Andre Jute
No real corpses were harmed in the assembly of my golem Worthless
Wieckless. I made him by stuffing a cow's bladder with pig offal. --
Creepy Mike LaFevre, Magnequest Transformers, Philadelphia

[Andre Jute]

On Nov 8, 6:32 am, Patrick Turner wrote:
Andre Jute wrote:
,,,but decided
not to complicate what I wrote with qualifications (no doubt Trevor
Wilson will next accuse me of *lying*!).

Shock, Horror, will someone tell you if you lied? how awful....

I don't mind if I'm wrong on some statement I made being corrected,
preferably politely of course. But Wilson accuses people of lying if
they don't include his fave Blow Jobs for Transvestites when they talk
about tubes; I just don't see how such an omission is a lie. If I want
to talk about BJTs, I can go to the alt.perverts.ss.gruppenfuhrer
newsgroup. But jokes aside, if we once open the door to a single mad
obsessive like Trevor Wilson, soon we'll have one-string ramkiekie
players around here demanding to know why they aren't mentioned every
time we mention a favourite recording of say, a Bach Cantata. The
Wilson Road runs from madness to madness.

And Cantata 199 to every cyclist: "My heart pumps a whole lotta
blood", freely translated (very) from the Cherman "Mein Herze swimt im
Blut."

Andre Jute
No real corpses were harmed in the assembly of my golem Worthless
Wieckless. I made him by stuffing a cow's bladder with pig offal. --
Creepy Mike LaFevre, Magnequest Transformers, Philadelphia

[Andre Jute]

On Nov 8, 11:22 am, RdM wrote:
Patrick Turner writes, inter alia, in
. au:

How many recordings of Vivaldi's Four Seasons does the world really
need?

Oh, well over 400, I should think ...http://svalander.se/vivaldi.htm

His wife is probably glad it keeps him out of the pub, judging by the
romantic photo she took of him.

In June 2002 I sent him details of one I had that he hadn't; not even on his
wanted list, so probably not known to him; Quattro Stagioni by the
Kammerensemble Cologne, on the Swiss Kutlu label; the lead violinist played a
1724 Stradivarius;

Never heard of the label, but I too have heard the KEC. I looked into
my catalogue and I have, in a collection of 6000 discs, three versions
of the Four Seasons, all the of them listed by your chum.

I bought the CD after the concert at the church they played
in here; I miss it very much, it having been left at a friends place which was
like a railway station with regular weekly music nights, and vanished ...

A close friend is one who can "borrow" your books and CDs permanently
without being struck off your Christmas card list.

I'd very much like a copy again, if anybody ever sees one:http://i17.tinypic.com/6ypj5zm.jpg

And perhaps some of the recording quality had to do with the equipment used:http://i11.tinypic.com/8evj28x.jpg(trimmed, much reduced quality of scan!)
(I had thought I might see if I could sneak a 40kb jpg into a text attachment
to the end of this message, re recent discussions, but nah, can't be bothered)

AJ may NB the Stax SR-Lambda Pro used for monitoring.

My ad agency owned a recording studio, which we bought in an (idle)
quest to give me more control over the quality of our advertisements.
There a set of Stax headphones was kept for me in a locked wooden box,
to which my boxers'n'sox dolly (the assistant who carried clean
panties for the girl and me so that we didn't smell too bad after four
days on my little plane), carried the key. I can't remember now what
model it was but, given the time, the late 1960s, it was probably
electret. I'm not into Stax history, which is pretty convoluted. But I
can say that a modern fixed bias Stax sounds just like the real deal
of ESL-63, whereas the electret of all those years ago didn't come to
within a mile of ESL-57. My Stax are absolutely amazing loudspeakers
compared to, for instance, the Senheisers I also have, but then they
should be, considering the price difference. But the Stax also leave
my old Bang & Olufsen dynamic headphones in the shade, and B&O don't
have the excuse that their product is cheaper.

Not sure if the comment on "transformerless" will win PT's heart, though!

One wonders if they mean "windingless" or if this is a mistranslation
for "not processed in any way".

An absolute proscription on transformers would be a new audiophool
obsession you have discovered, if true.

[No "tubes", either!]
--
Ross Matheson
(in nz, not zz...)

Andre Jute
"I was at a board meeting for the LA Chapter of the Audio Engineering
Society last night on XM Satellite radio audio and data transmission.
Sadly, we missed you there, and at the SMPTE and Acoustical Society
recent meetings as well. Everyone was asking, 'Where is that wonderful
Andre Jute? The world just doesn't rotate without him...'" -- John
Mayberry, Emmaco

[Arny Krueger]

"Eeyore" wrote in
message
Andre Jute wrote:

"Arny Krueger" wrote:
"Andre Jute" wrote in message

That's true, of course, but I think some, who were
educated in silicon only as Dave was, come to tube
amps with a silicon mindset that NFB is the cure-all,
that if a little is good, more must be better, and
lots will be superb.

Spoken like someone who lacks experience with how
coursed in feedback is taught.

Courses in feedback are rarely if ever couched in
either terms of either SS or tubes.

You're wanking, Krueger. By the time Dave was educated,
there were no more tubes. -- AJ

Irrelevant to feedback theory. Feedback works in the same
way, whatever active parts are in use. It is, after all,
merely maths at the end of the day.

Agreed.

In fact, feedback is rarely if ever taught using audio amplifiers as
examples. I've seen boats, helicopters, chemical processes, airplanes,
rockets and missiles all used to teach feedback. But never amplifiers,
either SS or tubed.

[Arny Krueger]

"Patrick Turner" wrote in message

Arny Krueger wrote:

"John Byrns" wrote in message
...
In article
, "Arny
Krueger" wrote:

"Dave" wrote in message
news:CfGWi.1359$8S5.242@edtnps82...

"Andre Jute" wrote in message
ups.com...

I know for a fact that people cannot
hear as much as 3/4 per cent second harmonic but can
hear that much odd harmonic very clearly, and many
people can hear or are made uncomfortable by 0.3 per
cent odd harmonics.

This order of harmonics issue is way overblown.
Doesn't matter whether it is
odd or even order nonlinearity, it all makes IM. IM is
generally aharmonic
and it all sounds bad.

But even order IM is much more obvious and annoying in
listening tests, although I suppose others may find odd
order IM more annoying, its probably partly a matter of
personal preference.

I've never seen that. Got a reference?

Here's what my analysis says:

Fundamentals: F1 and F2

Second Order IM: F1±F2, F2-F1

Third Order IM: 2F1±F2, 2F2±F1

Fourth Order IM: 2F1±2F2, 2F2±2F1

Fifth Order IM: 3F1±2F2, 3F2±2F1

Almost all sums and differences are inharmonic and
therefore likely to be objectionable.

Are not the IMD products somewhat different between an
amp with nearly all 2H THD
as opposed to one with mainly 3H THD?

Of course, but the discussion was not about picking nits, it was about
audibility. To provide what seems to be a much-needed refresher in what my
post said, it said that IM is more audibly objectionable because it is
inharmonic.

And then there is ordinary real music from instruments.
Presumably a fair amount of IMD is included.

Wrong, because in a live performance there is very little that mixes the
whole acoustic output of the musicians into a single signal and then puts
that single signal through a strongly nonlinear process.

And then the levels have to be considered.
If the THD is low, so is IMD and as the order of IMD
products become higher,
their levels get lower and lower.....

You don't get simple algebraic equations, do you? The equations above show
the actual scaling of the amplitude of the IM products which is unity,
invariant with order. In fact the higher orders of IM produce more different
products, each scaled by unity. Conservation of energy is preserved by how
the harmonics and fundamental add up as a function of time.

So you need to list the conditions and levels of a REAL
amp in a REAL world listening experience before the above
"reference" becomes meaningful.

False premise lead to a false conclusion.

[John Byrns]

In article ,
"Arny Krueger" wrote:

"Patrick Turner" wrote in message


And then there is ordinary real music from instruments.
Presumably a fair amount of IMD is included.

Wrong, because in a live performance there is very little that mixes the
whole acoustic output of the musicians into a single signal and then puts
that single signal through a strongly nonlinear process.

What about the ear of the listener, isn't IMD produced there that mixes
the whole acoustic output of the musicians?


Regards,

John Byrns

--
Surf my web pages at, http://fmamradios.com/

[Arny Krueger]

"John Byrns" wrote in message

In article ,
"Arny Krueger" wrote:

"Patrick Turner" wrote in
message

And then there is ordinary real music from instruments.
Presumably a fair amount of IMD is included.

Wrong, because in a live performance there is very
little that mixes the whole acoustic output of the
musicians into a single signal and then puts that single
signal through a strongly nonlinear process.

What about the ear of the listener, isn't IMD produced
there that mixes the whole acoustic output of the
musicians?

Hearing is indeed a nonlinear process, particularly at high levels. However,
at modest levels we can distinguish unmasked distortion products that are
like 60 dB down. I wouldn't call that "strongly nonlinear". When I say
"strongly nonlinear" I mean like several percent or more.

[Arny Krueger]

"Iain Churches" wrote in message
i.fi
"Andre Jute" wrote in message
ups.com...
Dave wrote:

"Andre Jute" wrote in message
ps.com...


The explanation is simple. Loop NFB causes artifacts
of ever lower magnitude but higher order.

Good example of majoring in the minors. Loop NFB drops nonlinearity by 20
dB or more. The equipment in question was not entirely free of higher order
nonliner distortion, and the secondary effect being obsessed over here
typically adds far less distortion than was already there.OTOH, the loop
feedback drops all nonlinear distortion by 20 dB. The net higher order
distortion is thus dramatically reduced.

These high
order distortions, even at 60dB below conscious
perception are very, very disturbing,

If they are so disturbing, why aren't the SET owners running out of the room
screaming every time they turn their MI amps on? Repeat, its not like SET
amps are free of higher order distoriton.They are based on tubes and tubes
are exponentially-based devices. The expansion of their theoretical
amplitude transfer function includes signficant higher-order terms, loop
feedback or not!

whereas second
harmonic up to three-quarter per cent cannot even be
distinguished by professional musicians. It is a
subliminal effect, and of course in pentode mode it is
exaggerated. People look at the total harmonic
distortion but in fact the higher harmonics must be
weighted much more heavily than the second harmonic to
account for its extraordinary subliminal effect, often
described as "edgineess" by professional musicians.

This was the explanation I was looking for. thank you.

Yes. That seems to be a good description of what is going
on, and explains why two similar tubes/valves of the same
type but by different makers may sound different. They
usually have the same or very similar THD but the
distortion spectra are sometimes surprisingly different. 2H is exactly an
octave of the fundamental, and so, in
"trace" amounts may be regarded as benign. 3H, 5H, 7H
and 9H, even at much lower levels are considerably more disturbing.

Same mythical thinking, repeated.

Repeat again, its not like SET amps are free of higher order distortion.They
are based on tubes and tubes are exponentially-based devices. The expansion
of their theoretical amplitude transfer function of a tubed amp includes
signficant higher-order terms, loop feedback or not!

Some years ago, the technical director of Svetlana sent
me the findings of a listening group with whom he had been working. Their
task was to evaluate 6CG7 tubes by different
makers, and put them in order of preference, so that they
could be measured and analysed. Although I was not able to obtain all
twelve makes on the list, with
some colleagues, I repeated the experiment.The differences
were most interesting. The interpretation of which is
"better" must be left to individual taste, but in general
terms, we ranked the tubes in roughly the same order as the Svetlana
listeners. In case you are wondering, the
RCA cleartop was the best sounding. It also had the lowest odd order
harmonics when measured in a mu follower circuit.

Yet another anecdote with questionable relevance.

You listen to your speakers, not your amp; I would
really advise you, unless you are married to these
insensitive speakers, first to get good sensitive
speakers you can live with forever, then build an amp
to suit them. If you have the space, an inexpensive
sensitive speaker you can build easily is The
Impresario on my netsite, url under my sig. EL84 are
particularly sweet in triode but of course pitifully
underpowered for insensitive speakers.

Yes, I know, efficient speakers are on my long-term
shopping list. My current speakers will run nicely on
15W (or even 12W). I have somewhat limited financial
means at my disposal for projects of this sort, but I do
like the look of the EL34 just because of its' high
power output. What's an acceptable value for distortion?

I have been involved in experiments on which panels of
listeners have been asked to differentiate between two identical
amplifiers, one set up to have 0.05% and the other 0.5%
THD. This is a difference of 20dB. No one, even the professionals on the
panel, could tell
which was which.

Probably not a well-run test. Tests like this are strongly depenendent on
the choice of program material. Most audiophile self-select program material
that sounds good on their home systems. If the person doing the selecting
has a system at home with relatively high nonlinear distortion, he's going
to pick recordings that are tolerant of relatively high nonlinear
distortion. So, they unconsciously desensitize the experiment because of
their preferences.


It is a long time since I have read the book, but IIRC
Olson states that listeners could not detect distortion
levels up to 1% on a music signal.

Again, that depends on context. How many CDs had Olson listened to by the
time he made that claim?

Right now I'm running a solid
state amp which is rated at 50W RMS with THD of 0.08%. I guess this
isn't a
reasonable target for a tube amp unless I run multiple
parallel UL PP pairs
per channel...

A while ago, I built a push pull parallel EL34 amp, with
two parallel pairs per channel. It can achieve 0.08% THD
at full power.

http://www.kolumbus.fi/iain.churches...em/C50_002.jpg

I don't know whether to laugh or cry.

And NFB up the kazoo. 0.1 per cent is a figure commonly
bandied about but I'm not overly impressed. I know for a
fact that people cannot hear as much as 3/4 per cent
second harmonic but can hear that much odd harmonic very
clearly, and many people can hear or are made
uncomfortable by 0.3 per cent odd harmonics. What you
want to do is not to measure at full power but at some
lower power where you will actually use the amp; 1W or
2.83V into 8ohm is a common level with even
semi-sensitive speakers.

Correct. A good PP valve/tube amp can manage 0.03% at 1W
While you should always measure and evaluate an amp in
detail, don't get bogged down in test bench measurements. Don't
expect with a tube amp to be able to apply 75dB of NFB, or
achieve a damping factor in three figures, and a badwidth DC to
daylight as you can in an SS amp. If you want that kind of sound,
buy a Crown:-)

Yes, only buy accurate amps if you are interested in accurate reproduction.

Happy to be of service to a hands-on audiophile. Good
luck.

Now we are getting back to RAT as it should be:-)

Full of misapprehensions and old wive's stories?

[Andre Jute]

On Nov 8, 3:23 pm, "Arny Krueger" wrote:
"Iain Churches" wrote in message

i.fi

"Andre Jute" wrote in message
oups.com...
Dave wrote:

"Andre Jute" wrote in message
roups.com...

The explanation is simple. Loop NFB causes artifacts
of ever lower magnitude but higher order.

Good example of majoring in the minors. Loop NFB drops nonlinearity by 20
dB or more. The equipment in question was not entirely free of higher order
nonliner distortion, and the secondary effect being obsessed over here
typically adds far less distortion than was already there.OTOH, the loop
feedback drops all nonlinear distortion by 20 dB. The net higher order
distortion is thus dramatically reduced.

We're not talking about the net number, Krueger. We're talking about
the effect of the composition of the residual distortion.

These high
order distortions, even at 60dB below conscious
perception are very, very disturbing,

If they are so disturbing, why aren't the SET owners
running out of the room
screaming every time they turn their MI amps on? Repeat, its not like SET
amps are free of higher order distoriton.They are based on tubes and tubes
are exponentially-based devices. The expansion of their theoretical
amplitude transfer function includes signficant higher-order terms, loop
feedback or not!

A conservatively designed and well-developed 300B amp can easily get
the third and higher harmonics down to 0.03 per cent without any loop
or stage feedback. I don't see how that is "significant" at all.

whereas second
harmonic up to three-quarter per cent cannot even be
distinguished by professional musicians. It is a
subliminal effect, and of course in pentode mode it is
exaggerated. People look at the total harmonic
distortion but in fact the higher harmonics must be
weighted much more heavily than the second harmonic to
account for its extraordinary subliminal effect, often
described as "edgineess" by professional musicians.

This was the explanation I was looking for. thank you.

Yes. That seems to be a good description of what is going
on, and explains why two similar tubes/valves of the same
type but by different makers may sound different. They
usually have the same or very similar THD but the
distortion spectra are sometimes surprisingly different. 2H is exactly an
octave of the fundamental, and so, in
"trace" amounts may be regarded as benign. 3H, 5H, 7H
and 9H, even at much lower levels are considerably more disturbing.

Same mythical thinking, repeated.

All right, Krueger, so you don't like psycho-acoustic truths
observable in repeatable tests disturbing your fauz certainties. So,
slumber on.

Repeat again, its not like SET amps are free of higher order distortion.They
are based on tubes and tubes are exponentially-based devices. The expansion
of their theoretical amplitude transfer function of a tubed amp includes
signficant higher-order terms, loop feedback or not!

So you keep saying, Krueger, but so far you have provided no proof of
your contention, which those of who bulld SETs know is untrue.

Some years ago, the technical director of Svetlana sent
me the findings of a listening group with whom he had been working. Their
task was to evaluate 6CG7 tubes by different
makers, and put them in order of preference, so that they
could be measured and analysed. Although I was not able to obtain all
twelve makes on the list, with
some colleagues, I repeated the experiment.The differences
were most interesting. The interpretation of which is
"better" must be left to individual taste, but in general
terms, we ranked the tubes in roughly the same order as the Svetlana
listeners. In case you are wondering, the
RCA cleartop was the best sounding. It also had the lowest odd order
harmonics when measured in a mu follower circuit.

Yet another anecdote with questionable relevance.

No, of the highest relevance. Such ranking experiments are of the
essence in psycho-acoustics. Conduct enough and a pattern emerges with
a very high level of confidence.

You listen to your speakers, not your amp; I would
really advise you, unless you are married to these
insensitive speakers, first to get good sensitive
speakers you can live with forever, then build an amp
to suit them. If you have the space, an inexpensive
sensitive speaker you can build easily is The
Impresario on my netsite, url under my sig. EL84 are
particularly sweet in triode but of course pitifully
underpowered for insensitive speakers.

Yes, I know, efficient speakers are on my long-term
shopping list. My current speakers will run nicely on
15W (or even 12W). I have somewhat limited financial
means at my disposal for projects of this sort, but I do
like the look of the EL34 just because of its' high
power output. What's an acceptable value for distortion?
I have been involved in experiments on which panels of
listeners have been asked to differentiate between two identical
amplifiers, one set up to have 0.05% and the other 0.5%
THD. This is a difference of 20dB. No one, even the professionals on the
panel, could tell
which was which.

Probably not a well-run test.

Really, Mr Arny "I spoke in error" Krueger. Will you now run through
all the possible alleged causes of error one by one, as on a previous
occasion you ran through all the alleged hearing disorders of
musicians when you didn't even know which group of musicians was under
discussion. Your known prejudices are so malicious as to destroy every
argument you make, Krueger.

Tests like this are strongly depenendent on
the choice of program material.

That is easily guarded against. You don't know what the program
material was.

Most audiophile self-select program material
that sounds good on their home systems.

Huh? I should think most audiophiles build their audio systems up from
components that sound good with the music they like (which you
bureaucratically call "program material").

If the person doing the selecting
has a system at home with relatively high nonlinear distortion, he's going
to pick recordings that are tolerant of relatively high nonlinear
distortion.

You don't know who picked the recordings for the test you're
condemning. You don't therefore know anything of his home system. You
are wittering into the void, Krueger.

So, they unconsciously desensitize the experiment because of
their preferences.

Wow! On a whole chain of ignorance of the particulars, you have now
constructed an accusation that someone "desensitized the experiment
because of their preferences". Prove your steps, Krueger, or withdraw
this dumb lie.

It is a long time since I have read the book, but IIRC
Olson states that listeners could not detect distortion
levels up to 1% on a music signal.

Again, that depends on context. How many CDs had Olson listened to by the
time he made that claim?

There were no CDs in Olson's time, Krueger. Get with the program, will
you? Your ignorance of the most basic research is embarrassing --
people might think we know you!

Right now I'm running a solid
state amp which is rated at 50W RMS with THD of 0.08%. I guess this
isn't a
reasonable target for a tube amp unless I run multiple
parallel UL PP pairs
per channel...
A while ago, I built a push pull parallel EL34 amp, with
two parallel pairs per channel. It can achieve 0.08% THD
at full power.
http://www.kolumbus.fi/iain.churches...em/C50_002.jpg

I don't know whether to laugh or cry.



And NFB up the kazoo. 0.1 per cent is a figure commonly
bandied about but I'm not overly impressed. I know for a
fact that people cannot hear as much as 3/4 per cent
second harmonic but can hear that much odd harmonic very
clearly, and many people can hear or are made
uncomfortable by 0.3 per cent odd harmonics. What you
want to do is not to measure at full power but at some
lower power where you will actually use the amp; 1W or
2.83V into 8ohm is a common level with even
semi-sensitive speakers.
Correct. A good PP valve/tube amp can manage 0.03% at 1W
While you should always measure and evaluate an amp in
detail, don't get bogged down in test bench measurements. Don't
expect with a tube amp to be able to apply 75dB of NFB, or
achieve a damping factor in three figures, and a badwidth DC to
daylight as you can in an SS amp. If you want that kind of sound,
buy a Crown:-)

Yes, only buy accurate amps if you are interested in accurate reproduction.

Anyone who can refer to music as "program material" as Krueger does
will probably be happy with a Crown amp. It says on p1 of the
instruction manual for the Crown: "In the operation of this amplifier
musical discrimination and taste are neither required nor encouraged
and will certainly not be fostered."

Happy to be of service to a hands-on audiophile. Good
luck.

Now we are getting back to RAT as it should be:-)

Full of misapprehensions and old wive's stories?

What you means is "old wives' tales". Note the plural and the
placement of the apostrophe.

Andre Jute
"I was at a board meeting for the LA Chapter of the Audio Engineering
Society last night on XM Satellite radio audio and data transmission.
Sadly, we missed you there, and at the SMPTE and Acoustical Society
recent meetings as well. Everyone was asking, 'Where is that wonderful
Andre Jute? The world just doesn't rotate without him...'" -- John
Mayberry, Emmaco

[Andre Jute]

On Nov 8, 3:23 pm, "Arny Krueger" wrote:
"Iain Churches" wrote in message

i.fi

"Andre Jute" wrote in message
oups.com...
Dave wrote:

"Andre Jute" wrote in message
roups.com...

The explanation is simple. Loop NFB causes artifacts
of ever lower magnitude but higher order.

Good example of majoring in the minors. Loop NFB drops nonlinearity by 20
dB or more. The equipment in question was not entirely free of higher order
nonliner distortion, and the secondary effect being obsessed over here
typically adds far less distortion than was already there.OTOH, the loop
feedback drops all nonlinear distortion by 20 dB. The net higher order
distortion is thus dramatically reduced.

We're not talking about the net number, Krueger. We're talking about
the effect of the composition of the residual distortion.

These high
order distortions, even at 60dB below conscious
perception are very, very disturbing,

If they are so disturbing, why aren't the SET owners
running out of the room
screaming every time they turn their MI amps on? Repeat, its not like SET
amps are free of higher order distoriton.They are based on tubes and tubes
are exponentially-based devices. The expansion of their theoretical
amplitude transfer function includes signficant higher-order terms, loop
feedback or not!

A conservatively designed and well-developed 300B amp can easily get
the third and higher harmonics down to 0.03 per cent without any loop
or stage feedback. I don't see how that is "significant" at all.

whereas second
harmonic up to three-quarter per cent cannot even be
distinguished by professional musicians. It is a
subliminal effect, and of course in pentode mode it is
exaggerated. People look at the total harmonic
distortion but in fact the higher harmonics must be
weighted much more heavily than the second harmonic to
account for its extraordinary subliminal effect, often
described as "edgineess" by professional musicians.

This was the explanation I was looking for. thank you.

Yes. That seems to be a good description of what is going
on, and explains why two similar tubes/valves of the same
type but by different makers may sound different. They
usually have the same or very similar THD but the
distortion spectra are sometimes surprisingly different. 2H is exactly an
octave of the fundamental, and so, in
"trace" amounts may be regarded as benign. 3H, 5H, 7H
and 9H, even at much lower levels are considerably more disturbing.

Same mythical thinking, repeated.

All right, Krueger, so you don't like psycho-acoustic truths
observable in repeatable tests disturbing your fauz certainties. So,
slumber on.

Repeat again, its not like SET amps are free of higher order distortion.They
are based on tubes and tubes are exponentially-based devices. The expansion
of their theoretical amplitude transfer function of a tubed amp includes
signficant higher-order terms, loop feedback or not!

So you keep saying, Krueger, but so far you have provided no proof of
your contention, which those of who bulld SETs know is untrue.

Some years ago, the technical director of Svetlana sent
me the findings of a listening group with whom he had been working. Their
task was to evaluate 6CG7 tubes by different
makers, and put them in order of preference, so that they
could be measured and analysed. Although I was not able to obtain all
twelve makes on the list, with
some colleagues, I repeated the experiment.The differences
were most interesting. The interpretation of which is
"better" must be left to individual taste, but in general
terms, we ranked the tubes in roughly the same order as the Svetlana
listeners. In case you are wondering, the
RCA cleartop was the best sounding. It also had the lowest odd order
harmonics when measured in a mu follower circuit.

Yet another anecdote with questionable relevance.

No, of the highest relevance. Such ranking experiments are of the
essence in psycho-acoustics. Conduct enough and a pattern emerges with
a very high level of confidence.

You listen to your speakers, not your amp; I would
really advise you, unless you are married to these
insensitive speakers, first to get good sensitive
speakers you can live with forever, then build an amp
to suit them. If you have the space, an inexpensive
sensitive speaker you can build easily is The
Impresario on my netsite, url under my sig. EL84 are
particularly sweet in triode but of course pitifully
underpowered for insensitive speakers.

Yes, I know, efficient speakers are on my long-term
shopping list. My current speakers will run nicely on
15W (or even 12W). I have somewhat limited financial
means at my disposal for projects of this sort, but I do
like the look of the EL34 just because of its' high
power output. What's an acceptable value for distortion?
I have been involved in experiments on which panels of
listeners have been asked to differentiate between two identical
amplifiers, one set up to have 0.05% and the other 0.5%
THD. This is a difference of 20dB. No one, even the professionals on the
panel, could tell
which was which.

Probably not a well-run test.

Really, Mr Arny "I spoke in error" Krueger. Will you now run through
all the possible alleged causes of error one by one, as on a previous
occasion you ran through all the alleged hearing disorders of
musicians when you didn't even know which group of musicians was under
discussion. Your known prejudices are so malicious as to destroy every
argument you make, Krueger.

Tests like this are strongly depenendent on
the choice of program material.

That is easily guarded against. You don't know what the program
material was.

Most audiophile self-select program material
that sounds good on their home systems.

Huh? I should think most audiophiles build their audio systems up from
components that sound good with the music they like (which you
bureaucratically call "program material").

If the person doing the selecting
has a system at home with relatively high nonlinear distortion, he's going
to pick recordings that are tolerant of relatively high nonlinear
distortion.

You don't know who picked the recordings for the test you're
condemning. You don't therefore know anything of his home system. You
are wittering into the void, Krueger.

So, they unconsciously desensitize the experiment because of
their preferences.

Wow! On a whole chain of ignorance of the particulars, you have now
constructed an accusation that someone "desensitized the experiment
because of their preferences". Prove your steps, Krueger, or withdraw
this dumb lie.

It is a long time since I have read the book, but IIRC
Olson states that listeners could not detect distortion
levels up to 1% on a music signal.

Again, that depends on context. How many CDs had Olson listened to by the
time he made that claim?

There were no CDs in Olson's time, Krueger. Get with the program, will
you? Your ignorance of the most basic research is embarrassing --
people might think we know you!

Right now I'm running a solid
state amp which is rated at 50W RMS with THD of 0.08%. I guess this
isn't a
reasonable target for a tube amp unless I run multiple
parallel UL PP pairs
per channel...
A while ago, I built a push pull parallel EL34 amp, with
two parallel pairs per channel. It can achieve 0.08% THD
at full power.
http://www.kolumbus.fi/iain.churches...em/C50_002.jpg

I don't know whether to laugh or cry.



And NFB up the kazoo. 0.1 per cent is a figure commonly
bandied about but I'm not overly impressed. I know for a
fact that people cannot hear as much as 3/4 per cent
second harmonic but can hear that much odd harmonic very
clearly, and many people can hear or are made
uncomfortable by 0.3 per cent odd harmonics. What you
want to do is not to measure at full power but at some
lower power where you will actually use the amp; 1W or
2.83V into 8ohm is a common level with even
semi-sensitive speakers.
Correct. A good PP valve/tube amp can manage 0.03% at 1W
While you should always measure and evaluate an amp in
detail, don't get bogged down in test bench measurements. Don't
expect with a tube amp to be able to apply 75dB of NFB, or
achieve a damping factor in three figures, and a badwidth DC to
daylight as you can in an SS amp. If you want that kind of sound,
buy a Crown:-)

Yes, only buy accurate amps if you are interested in accurate reproduction.

Anyone who can refer to music as "program material" as Krueger does
will probably be happy with a Crown amp. It says on p1 of the
instruction manual for the Crown: "In the operation of this amplifier
musical discrimination and taste are neither required nor encouraged
and will certainly not be fostered."

Happy to be of service to a hands-on audiophile. Good
luck.

Now we are getting back to RAT as it should be:-)

Full of misapprehensions and old wive's stories?

What you means is "old wives' tales". Note the plural and the
placement of the apostrophe.

Andre Jute
"I was at a board meeting for the LA Chapter of the Audio Engineering
Society last night on XM Satellite radio audio and data transmission.
Sadly, we missed you there, and at the SMPTE and Acoustical Society
recent meetings as well. Everyone was asking, 'Where is that wonderful
Andre Jute? The world just doesn't rotate without him...'" -- John
Mayberry, Emmaco

[Andre Jute]

On Nov 8, 6:32 am, Patrick Turner wrote:
Andre Jute wrote:
,,,but decided
not to complicate what I wrote with qualifications (no doubt Trevor
Wilson will next accuse me of *lying*!).

Shock, Horror, will someone tell you if you lied? how awful....

I don't mind if I'm wrong on some statement I made being corrected,
preferably politely of course. But Wilson accuses people of lying if
they don't include his fave Blow Jobs for Transvestites when they talk
about tubes; I just don't see how such an omission is a lie. If I want
to talk about BJTs, I can go to the alt.perverts.ss.gruppenfuhrer
newsgroup. But jokes aside, if we once open the door to a single mad
obsessive like Trevor Wilson, soon we'll have one-string ramkiekie
players around here demanding to know why they aren't mentioned every
time we mention a favourite recording of say, a Bach Cantata. The
Wilson Road runs from madness to madness.

And Cantata 199 to every cyclist: "My heart pumps a whole lotta
blood", freely translated (very) from the Cherman "Mein Herze swimt im
Blut."

Andre Jute
No real corpses were harmed in the assembly of my golem Worthless
Wieckless. I made him by stuffing a cow's bladder with pig offal. --
Creepy Mike LaFevre, Magnequest Transformers, Philadelphia

[Iain Churches[_2_]]

"John Byrns" wrote in message
...
In article ,
"Arny Krueger" wrote:

"Patrick Turner" wrote in message


And then there is ordinary real music from instruments.
Presumably a fair amount of IMD is included.

Wrong, because in a live performance there is very little that mixes the
whole acoustic output of the musicians into a single signal and then puts
that single signal through a strongly nonlinear process.

What about the ear of the listener, isn't IMD produced there that mixes
the whole acoustic output of the musicians?

Yes indeed. I have experienced this many times. It is not audible from the
audience seats. See my reply to Arny.

Iain

[Iain Churches[_2_]]

"Arny Krueger" wrote in message
. ..


John wrote:
And then there is ordinary real music from instruments.
Presumably a fair amount of IMD is included.

Wrong, because in a live performance there is very little that mixes the
whole acoustic output of the musicians into a single signal and then puts
that single signal through a strongly nonlinear process.


Arny, Try this experiment. Sit amongst an orchestra during rehearsals or
recording. Place your chair at the back and to the right of the French horn
section, where the microphone would be on a multi-mic setup. Four horns
are good, five horns are better. Sibelius 5, Op 82 Eb is a perfect example.

Then tell me there is no acoustic IMD.

Cordially,

Iain