I know, I know..... this is real old tube stuff and there may be
better stuff out there now......

But, for the sake of argument, the Audio Research SP-11 preamp
frequently gets much high praise. You don't hear as much about the
similarly configured ARC SP-15 pre-amp. I would like to get one or the
other.

Would anyone care to offer their opinion or experience as
to which of the two provides the better sound path for
CD's versus for vinyl?

Thanks for your comments.
--
....R L

YxYx" to reply wrote:
I know, I know..... this is real old tube stuff and there may be
better stuff out there now......

But, for the sake of argument, the Audio Research SP-11 preamp
frequently gets much high praise. You don't hear as much about the
similarly configured ARC SP-15 pre-amp. I would like to get one or
the
other.

Would anyone care to offer their opinion or experience as
to which of the two provides the better sound path for
CD's versus for vinyl?

Thanks for your comments.
--
...R L

They are very very similar in sound. If you like one you should like
the other. They have identical phono stages. The only differences are
in the line stage and that is mostly a matter of different parts and
materials. Personally I like the SP 10 better than either and it will
cost you less.

Scott Wheeler

a écrit :

Scott Wheeler

Congratulation, your new nickname is really funnier than the previous one.

YxYx" to reply wrote in message
...
I know, I know..... this is real old tube stuff and there may be
better stuff out there now......

But, for the sake of argument, the Audio Research SP-11 preamp frequently
gets much high praise. You don't hear as much about the similarly
configured ARC SP-15 pre-amp. I would like to get one or the other.

Would anyone care to offer their opinion or experience as
to which of the two provides the better sound path for
CD's versus for vinyl?

Thanks for your comments.

**Would you prefer to be killed by firing squad, or lethal injection?

Why would you restrict your choices, to two, faulty products? Expand your
horizons a little.


--
Trevor Wilson
www.rageaudio.com.au

Trevor Wilson wrote:


**Would you prefer to be killed by firing squad, or lethal injection?

Why would you restrict your choices, to two, faulty products? Expand
your
horizons a little.


And just why are they faulty?

wrote in message
oups.com...

Trevor Wilson wrote:


**Would you prefer to be killed by firing squad, or lethal injection?

Why would you restrict your choices, to two, faulty products? Expand
your
horizons a little.


And just why are they faulty?

**Because both colour the music. The SP11 is the lesser of the two products.
There are other, far more sanely priced products, which do not colour the
sound. If the OP specifically requires a tube preamp (for whatever bizarre
reason), then he should audition a Conrad Johnson Premier 16. For a tube
preamp, it is remarkably neutral.


--
Trevor Wilson
www.rageaudio.com.au

Trevor Wilson wrote:


snip


And just why are they faulty?

**Because both colour the music. The SP11 is the lesser of the two
products.
There are other, far more sanely priced products, which do not colour
the
sound. If the OP specifically requires a tube preamp (for whatever
bizarre
reason), then he should audition a Conrad Johnson Premier 16. For a
tube
preamp, it is remarkably neutral.

And how, or in what way, do they "colour" the music? Do they have bass
or treble rolloff, high distortion, or compress the dynamics of the
signal?

What does the c-j Premier 16 do that other preamps, commercial or
homemade, do not (or what does it not do that they do), and, why?

FWIW while I believe that listeners who listen exclusively to CDs
should have no preamp-they should purchase or modify a CD player to
directly drive their power amps in fine fashion(or buy an integrated,
which stereo amps should be anyway)-my own Marantz 7 clone audibly
outperforms the majority of preamps selling for any amount of money.
Only its phono section is less than magnificent. I listen to CDs,
vinyl, and other sources and while I have auditioned very expensive
preamps I notice little or no difference between them and what I have.
Of course this is a sighted eval and so hardly scientific, but it is my
subjective judgment that many if not most c-j, ARC, and other high
dollar tube products as well as many solid state products costing the
price of a new car are not superior to what you can cobble up at home.

Incidentally it's worth noting that certain manufacturers of tube
power amplifiers specifically enjoin users from using solid state
preamps because small DC offsets could be propagated through their
amplifier for long enough to debias the finals.

wrote in message
oups.com...

Trevor Wilson wrote:


snip


And just why are they faulty?

**Because both colour the music. The SP11 is the lesser of the two
products.
There are other, far more sanely priced products, which do not colour
the
sound. If the OP specifically requires a tube preamp (for whatever
bizarre
reason), then he should audition a Conrad Johnson Premier 16. For a
tube
preamp, it is remarkably neutral.

And how, or in what way, do they "colour" the music? Do they have bass
or treble rolloff, high distortion, or compress the dynamics of the
signal?

**They distort and add microphonics to the signal.


What does the c-j Premier 16 do that other preamps, commercial or
homemade, do not (or what does it not do that they do), and, why?

**The CJ goes to heroic lengths to manintain linearity and isolation for the
tubes. The PCBs are mounted with compliant rubber bits. ARC does not do
this. As a result, the ARC designs suffer with microphonic problems. The
image, for instance, becomes bloated.


FWIW while I believe that listeners who listen exclusively to CDs
should have no preamp-they should purchase or modify a CD player to
directly drive their power amps in fine fashion(or buy an integrated,
which stereo amps should be anyway)-my own Marantz 7 clone audibly
outperforms the majority of preamps selling for any amount of money.
Only its phono section is less than magnificent. I listen to CDs,
vinyl, and other sources and while I have auditioned very expensive
preamps I notice little or no difference between them and what I have.
Of course this is a sighted eval and so hardly scientific, but it is my
subjective judgment that many if not most c-j, ARC, and other high
dollar tube products as well as many solid state products costing the
price of a new car are not superior to what you can cobble up at home.

**Spoken, no doubt, by one who has yet to hear a CJ Prem 16. The Prem 16 is
as good as the best SS preamps I have ever heard. It is VERY quiet and very
low distortion.


Incidentally it's worth noting that certain manufacturers of tube
power amplifiers specifically enjoin users from using solid state
preamps because small DC offsets could be propagated through their
amplifier for long enough to debias the finals.

**Only VERY poorly implemented SS preamps suffer such problems.
Additionally, the vast majority of tube power amps employ an input coupling
cap, which makes your statement simply absurd.


--
Trevor Wilson
www.rageaudio.com.au

Trevor Wilson wrote:

snip

**Spoken, no doubt, by one who has yet to hear a CJ Prem 16. The Prem
16 is
as good as the best SS preamps I have ever heard. It is VERY quiet
and very
low distortion.



No, sure haven't. I'm pretty pleased with my homemade Marantz 7. It
has a toroidal power supply mounted outboard and ceramic sockets and
tag boards (no PCBs) pulled out of dead WE microwave telco equipment.
Counting the precision stepped attenuator I've got a whopping $150 in
this thing.

I have compared it to a couple of ARC units and IMO it sounded better,
but then I'm biased.


Incidentally it's worth noting that certain manufacturers of tube
power amplifiers specifically enjoin users from using solid state
preamps because small DC offsets could be propagated through their
amplifier for long enough to debias the finals.

**Only VERY poorly implemented SS preamps suffer such problems.
Additionally, the vast majority of tube power amps employ an input
coupling
cap, which makes your statement simply absurd.


Yes, but the manufacturer in question uses very large values of cap so
that a DC offset can swamp the output stage long enough to cause an
output tube to pull a lot of current long enough to shorten its life.
The fix is to replace the cap in question, of course, but you paid for
a manufactured product, not a kit...

wrote in message
oups.com...

Trevor Wilson wrote:

snip

**Spoken, no doubt, by one who has yet to hear a CJ Prem 16. The Prem
16 is
as good as the best SS preamps I have ever heard. It is VERY quiet
and very
low distortion.



No, sure haven't. I'm pretty pleased with my homemade Marantz 7. It
has a toroidal power supply mounted outboard and ceramic sockets and
tag boards (no PCBs) pulled out of dead WE microwave telco equipment.
Counting the precision stepped attenuator I've got a whopping $150 in
this thing.

**Good for you. I've built a few tube preamps. None could approach the S/N
figures of a decent SS one. Nor distortion, for that matter.


I have compared it to a couple of ARC units and IMO it sounded better,
but then I'm biased.

**Then we agree. The ARC SP-11 and SP-15 are both flawed products. You
SHOULD listen to a Prem 16, before consigning all commercial tube preamps to
the trash heap. It is a VERY good preamp. Of course, that it is possible to
buy an alternate product, for significantly less money (in SS), then that is
another story.



Incidentally it's worth noting that certain manufacturers of tube
power amplifiers specifically enjoin users from using solid state
preamps because small DC offsets could be propagated through their
amplifier for long enough to debias the finals.

**Only VERY poorly implemented SS preamps suffer such problems.
Additionally, the vast majority of tube power amps employ an input
coupling
cap, which makes your statement simply absurd.


Yes, but the manufacturer in question uses very large values of cap so
that a DC offset can swamp the output stage long enough to cause an
output tube to pull a lot of current long enough to shorten its life.
The fix is to replace the cap in question, of course, but you paid for
a manufactured product, not a kit...

**And again: Only INCOMPETENTLY designed SS products produce any significant
amounts of DC offset. For the record: The potential for DC offset problems
is FAR more likely with a tube preamp.


--
Trevor Wilson
www.rageaudio.com.au

wrote in message

Incidentally it's worth noting that certain manufacturers of tube
power amplifiers specifically enjoin users from using solid state
preamps because small DC offsets could be propagated through their
amplifier for long enough to debias the finals.

Ironically, debiasing of this kind is not uncommonly used in an attempt to
reduce crossover distortion in ICs.

wrote in message
oups.com...

YxYx" to reply wrote:
I know, I know..... this is real old tube stuff and there may be
better stuff out there now......

But, for the sake of argument, the Audio Research SP-11 preamp
frequently gets much high praise. You don't hear as much about the
similarly configured ARC SP-15 pre-amp. I would like to get one or
the
other.

Would anyone care to offer their opinion or experience as
to which of the two provides the better sound path for
CD's versus for vinyl?

Thanks for your comments.
--
...R L

They are very very similar in sound. If you like one you should like
the other. They have identical phono stages. The only differences are
in the line stage and that is mostly a matter of different parts and
materials. Personally I like the SP 10 better than either and it will
cost you less.

Scott Wheeler


You're right the SP11 got cult status for very good reason and still sought
after, just google for user reviews that will tell you all you need to know.
I've had plenty of cash offers:-) It is a hybrid design so not just tube
The tubes though have to be carefully chosen for low microphony and to use a
support platform. I use isolation courtesy of Messrs Townsend's plus air
pods stacked. If you do this you will be rewarded with exceptional
performance.
I've tried many other preamps in the interim but nothing else has convinced
me yet.

Mike

Why, when a question is posed, would someone take the time to just slam
the question. Nothing productive in that. Obviously I am ignorant, or I
wouldn't have asked the question. But there IS a cure for ignorance.

Have't you ever heard "There are no dumb questions - just dumb answers"


wrote:
Trevor Wilson wrote:


**Would you prefer to be killed by firing squad, or lethal injection?

Why would you restrict your choices, to two, faulty products? Expand

your

horizons a little.



And just why are they faulty?

said:

Incidentally it's worth noting that certain manufacturers of tube
power amplifiers specifically enjoin users from using solid state
preamps because small DC offsets could be propagated through their
amplifier for long enough to debias the finals.

Next to impossible, since every tube amp (at least that I know of) has
coupling capacitors somewhere in the signal path.

In the very rare occasion that an amp doesn't have coupling caps,
(could be possible with a capacitorless OTL), the danger you describe
could happen.
But then again, only the output rail would swing up or down, not the
bias.

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Trevor Wilson" said:

And how, or in what way, do they "colour" the music? Do they have bass
or treble rolloff, high distortion, or compress the dynamics of the
signal?

**They distort and add microphonics to the signal.

Tell me how much distortion (THD and/or IMD) an SRPP stage with 6DJ8
has.
Microphonics can be avoided by selecting good tubes.

**Spoken, no doubt, by one who has yet to hear a CJ Prem 16. The Prem 16 is
as good as the best SS preamps I have ever heard. It is VERY quiet and very
low distortion.

Then what's the point of using tubes?

Incidentally it's worth noting that certain manufacturers of tube
power amplifiers specifically enjoin users from using solid state
preamps because small DC offsets could be propagated through their
amplifier for long enough to debias the finals.

**Only VERY poorly implemented SS preamps suffer such problems.
Additionally, the vast majority of tube power amps employ an input coupling
cap, which makes your statement simply absurd.

Agreed.

--
Sander de Waal
" SOA of a KT88? Sufficient. "

said:

I have compared it to a couple of ARC units and IMO it sounded better,
but then I'm biased.

In class A, no doubt ;-)

Yes, but the manufacturer in question uses very large values of cap so
that a DC offset can swamp the output stage long enough to cause an
output tube to pull a lot of current long enough to shorten its life.

Nope.
Imagine what happens when the amp is switched on (or off), or a loud
thump from switching or a loud bass drum is processed by the amp.
The time constant of a typical RC combination of 0.5 uF and 100k in
the grid path of a power tube is 20 s.
However, one can't neglect the grid current that will occur at or
above a grid voltage of 0 V, thereby draining the charge of the
coupling cap very fast.
If the impulse at the grid is in the opposite direction, which is
likely with a positive going signal at the anode of the driver tube,
the power tube will be cut off and no danger of excessive current
through it is present.

The fix is to replace the cap in question, of course, but you paid for
a manufactured product, not a kit...

The cap will survive things like that, unlike any DC coupled solid
state amplifier and/or the connected speaker.............

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"YxYx\" to reply said:

Why, when a question is posed, would someone take the time to just slam
the question. Nothing productive in that. Obviously I am ignorant, or I
wouldn't have asked the question. But there IS a cure for ignorance.

Have't you ever heard "There are no dumb questions - just dumb answers"

"Ignorance is no excuse for a lack of knowledge". *

A Krueger, RAO, somewhere last year.


* spelling errors corrected for the sake of clarity.

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Sander deWaal" wrote in message
...
"Trevor Wilson" said:

And how, or in what way, do they "colour" the music? Do they have bass
or treble rolloff, high distortion, or compress the dynamics of the
signal?

**They distort and add microphonics to the signal.

Tell me how much distortion (THD and/or IMD) an SRPP stage with 6DJ8
has.
Microphonics can be avoided by selecting good tubes.

**Wrong. ALL tubes are microphonic. CJ realise this fact and the entire
substructure of the preamp is mounted with compliant material.


**Spoken, no doubt, by one who has yet to hear a CJ Prem 16. The Prem 16
is
as good as the best SS preamps I have ever heard. It is VERY quiet and
very
low distortion.

Then what's the point of using tubes?

**There is none, of course.


Incidentally it's worth noting that certain manufacturers of tube
power amplifiers specifically enjoin users from using solid state
preamps because small DC offsets could be propagated through their
amplifier for long enough to debias the finals.

**Only VERY poorly implemented SS preamps suffer such problems.
Additionally, the vast majority of tube power amps employ an input
coupling
cap, which makes your statement simply absurd.

Agreed.

**Good.


--
Trevor Wilson
www.rageaudio.com.au

"Sander deWaal" wrote in message
...
"Trevor Wilson" said:

**They distort and add microphonics to the signal.

Tell me how much distortion (THD and/or IMD) an SRPP stage with 6DJ8
has.
Microphonics can be avoided by selecting good tubes.

**Wrong. ALL tubes are microphonic. CJ realise this fact and the entire
substructure of the preamp is mounted with compliant material.

That of course is always a good idea.
But it is entirely possible to design a SRPP, yes even a CC circuit
with negligible distortion.

**Yep. CJ proved that, with the Prem 16. ARC did not manage it with either
the SP-11 or the SP-15. CJ went one step further and alleviated the problem
of microphonics, which afflicts ALL tube preamps.


--
Trevor Wilson
www.rageaudio.com.au

YxYx" to reply wrote in message
...
Why, when a question is posed, would someone take the time to just slam
the question. Nothing productive in that. Obviously I am ignorant, or I
wouldn't have asked the question. But there IS a cure for ignorance.

Have't you ever heard "There are no dumb questions - just dumb answers"

**I've heard that old chestnut before. That, of course, does not make it any
mroe correct. There are, indeed, dumb questions.


--
Trevor Wilson
www.rageaudio.com.au

First off, there's little question in my mind that tube RIAA stages
can and frequently do deliver superior subjective sound over many solid
state ones. This fits with Hamm et al.

Secondly, as I indicated before, I think the question of line level
stages is best solved by minimizing the circuit path and the number of
interconnects, i.e. no preamp at all. Tuners, tape machines, and DACs
(whether separate or built in) should be capable of directly driving
most power amps with which they may reasonably be expected to used
(i.e. 1Vpp into any bridging load single ended or +4dBm into 600 ohm
balanced or not) or the stereo amp should have a volume control and
switchable inputs (i.e. a line stage integrated). The preamp should
ideally be an obsolete critter. Especially in an era where so many
"audiophiles" have no analog sources.

(A corollary is the "passive preamp", another way of saying a
switchbox and volume control. I am sometimes inclined to think we'd be
better off doing it "telco style"-no, not doggystyling Lily Tomlin, but
putting WECO double jacks on the front and patching them as desired as
is still done in pro audio and even video with 75 ohm BNC cables in
patchbays.)

Thirdly and most significantly, I really have come to the conclusion
that whether the phono stage is solid state or tube is less important
than whether-or I should say _how far_-it is located from the
cartridge. Phono stages should be as close as possible as long as they
aren't too close to the table's motor. Putting a good solid state phono
stage in the table itself or immediately outboard, is the way to go. My
next project is going to be a phono stage in a little box using two
stage passive, as opposed to Baxandall, RIAA. If I use a variable lab
supply I can build it so I can use triode tubes or N-channel FETs and
experiment easily (and indeed if I use a 90-volt B+ as recommended with
6DJ8's I could probably just find a suitable FET that will live at that
source voltage.)

And as an aside, what magic mojo does c-j do that a hobbyist couldn't?

wrote in message
oups.com...

First off, there's little question in my mind that tube RIAA stages
can and frequently do deliver superior subjective sound over many solid
state ones. This fits with Hamm et al.

**Prior to ca. 1975, that may have been true. It is no longer the case and
has not been so, for many years. Moreover, ALL tubes have major problems
dealing with such low signal levels, due to the microphonic nature of all
tubes. Transistors make MUCH more sense, in this application.


Secondly, as I indicated before, I think the question of line level
stages is best solved by minimizing the circuit path and the number of
interconnects, i.e. no preamp at all. Tuners, tape machines, and DACs
(whether separate or built in) should be capable of directly driving
most power amps with which they may reasonably be expected to used
(i.e. 1Vpp into any bridging load single ended or +4dBm into 600 ohm
balanced or not) or the stereo amp should have a volume control and
switchable inputs (i.e. a line stage integrated). The preamp should
ideally be an obsolete critter. Especially in an era where so many
"audiophiles" have no analog sources.

**An opinion you get to have. I prefer to keep 2kVA+ power transformers well
away from low level stages, wherever possible.


(A corollary is the "passive preamp", another way of saying a
switchbox and volume control. I am sometimes inclined to think we'd be
better off doing it "telco style"-no, not doggystyling Lily Tomlin, but
putting WECO double jacks on the front and patching them as desired as
is still done in pro audio and even video with 75 ohm BNC cables in
patchbays.)

**Been there, done that. All passive controllers possess their own set of
problems. An active preamp can easily be made to provide essentially zero
distortion, yet provide a 0 Ohm output impedance. A device with a varying
output impedance (ie: a passive controller) is not a real smart idea, when
using long interconnects.


Thirdly and most significantly, I really have come to the conclusion
that whether the phono stage is solid state or tube is less important
than whether-or I should say _how far_-it is located from the
cartridge. Phono stages should be as close as possible as long as they
aren't too close to the table's motor. Putting a good solid state phono
stage in the table itself or immediately outboard, is the way to go. My
next project is going to be a phono stage in a little box using two
stage passive, as opposed to Baxandall, RIAA. If I use a variable lab
supply I can build it so I can use triode tubes or N-channel FETs and
experiment easily (and indeed if I use a 90-volt B+ as recommended with
6DJ8's I could probably just find a suitable FET that will live at that
source voltage.)

And as an aside, what magic mojo does c-j do that a hobbyist couldn't?

**Nothing, I can see. It uses a relay matrix volume control, with Vishay
resistors, capable of 1dB steps. Excellent, low noise power supplies, DC
filaments, etc, etc. Programming a micro to control the volume an input
selection (Also with relays) would be difficult for a hobbyist to organise.
Ditto, the high grade PCBs, isolated from the main chassis. Difficult, but
certainly not impossible.


--
Trevor Wilson
www.rageaudio.com.au

wrote in message
oups.com

First off, there's little question in my mind that tube RIAA stages
can and frequently do deliver superior subjective sound over many
solid state ones.

Just an unsupported opinion.

This fits with Hamm et al.

The Hamm paper was first published in the late 1970s. It is loaded with
examples of technology that was outdated when it was published. That was
almost 30 years ago. Hamm proponents would like us to believe that there
were no relevant advances in solid state electronics over the past 30 years.

Hamm proponents believe, as Chief Engineer Scott said, 'you canna
change the laws of physics". While solid state HAS improved and DOES
do a fine job in many and maybe most applications, the electrical
toughness and high operating voltages of tubes have still not been
wholly eclipsed. The bottom line is that while the details have
changed, the fact that Hamm even publicly asked what was then a very
awkward question, and proceeded to publish as he did, should be held in
high esteem forever even if solid state devices do come to do all the
tube stuff better than the tubes did. They absolutely did not then and
they don't fully even today, although there's no question the situation
has improved somewhat. Good solid state gear stilll isn't cheap, and is
rarely bulletproof-failures tend to be catastrophic and take a lot of
moxie to fix (and redesign around obsolete semi's.)

wrote in message
oups.com...
Hamm proponents believe, as Chief Engineer Scott said, 'you canna
change the laws of physics". While solid state HAS improved and DOES
do a fine job in many and maybe most applications, the electrical
toughness and high operating voltages of tubes have still not been
wholly eclipsed.

**Sort of. Tubes are still a good choice for high power transmission and
radar equipment. For anything under a couple of MHz, SS is the way to go. At
ANY power level.

The bottom line is that while the details have
changed, the fact that Hamm even publicly asked what was then a very
awkward question, and proceeded to publish as he did, should be held in
high esteem forever even if solid state devices do come to do all the
tube stuff better than the tubes did. They absolutely did not then and
they don't fully even today, although there's no question the situation
has improved somewhat. Good solid state gear stilll isn't cheap, and is
rarely bulletproof-failures tend to be catastrophic and take a lot of
moxie to fix (and redesign around obsolete semi's.)

**Cite please. After you cite that, I will relate my experiences with tube
equipment using obsolete tubes. The last repair job cost US$500.00, to fix a
3 Watt/channel, push pull tube amp. The tubes were obsolete and the only guy
on the planet who had them, stuck it to me. The guy who rewound the output
transformers charged like a wounded bull. Then there was this Luxman, using
unique Triodes. I had to rebuild the thing, using KT88s in Triode mode. It
cost the owner big time.

Tell me about obsolete semis. Tell me about YOUR direct experiences with
them.


--
Trevor Wilson
www.rageaudio.com.au

"Talk to me, Lee DeForest. Tell me all about it!"

wrote in message
oups.com...
"Talk to me, Lee DeForest. Tell me all about it!"

**Strawman noted.


--
Trevor Wilson
www.rageaudio.com.au

A quote from "Diamonds are a Girl's Best Friend",i.e. a little humor,
as opposed to a strawman.

Offhand I can't think of an obso semi because I am primarily a
homebrewer and usually if a solid state project doesn't have readily
available parts I don't start in the first place. They are definitely
out there though. Usually it's an IC for which there is a similar part,
but it doesn't match the PCB layout at all. You wind up building a
kluge board. I have worked on solid state home organs where the
generator IC is NLA, but a third party has a prefab module (potted of
course) that replaces it. The organ in question also had a dead solid
state power amp but we took it and the speaker out and put in a line
level out. The owner then just used a commodity keyboard/bass combo
amp, with complete satisfaction.
What kind of tube was it your three watt push pull amp used?

wrote in message
oups.com...
A quote from "Diamonds are a Girl's Best Friend",i.e. a little humor,
as opposed to a strawman.

Offhand I can't think of an obso semi because

**I accept your admission that you cannot provide an example. I figured you
could not. I can supply literally dozens of examples of obsolete tubes.
Here's another:

A few years ago, I serviced an ARC power amp. I can't recall the model
number. It required a new set of output tubes. I fitted some US made NOS
6550 tubes. I was then unable to pull the amp into the correct range of bias
(it uses LEDs to indicate correct bias current). A 'phone call to the local
distributors and I was able to (un)happily inform my client that the repair
bill had just gine up by AUS$1,000.00, since I had to fit a mod to the amp,
so it could cope with a 6550, other than a Sylvania branded one. YIKES! The
list goes on. I promise you that obsolete semis ARE a problem, but mostly
with mid-fi equipment. VERY rarely with decent equipment, which uses
descrete output stages. Tube equipment, OTOH, is a whole 'nuther ball game.
As all those fools who spent big bucks on those silly Musical Fidelity
hybrid products will surely discover.

I am primarily a
homebrewer and usually if a solid state project doesn't have readily
available parts I don't start in the first place. They are definitely
out there though. Usually it's an IC for which there is a similar part,
but it doesn't match the PCB layout at all.

**Example please.

You wind up building a
kluge board. I have worked on solid state home organs where the
generator IC is NLA, but a third party has a prefab module (potted of
course) that replaces it. The organ in question also had a dead solid
state power amp but we took it and the speaker out and put in a line
level out. The owner then just used a commodity keyboard/bass combo
amp, with complete satisfaction.

**Hang on a sec! We're discussing audio amplification equipment, not musical
instruments.

What kind of tube was it your three watt push pull amp used?

**Buggered if I can recall. The whole job was a nightmare. I'd rather forget
about it. I can go through my records and find out, if you really don't
believe me.


--
Trevor Wilson
www.rageaudio.com.au

"Trevor Wilson" wrote in message
...
: **Good for you. I've built a few tube preamps. None could approach the S/N
: figures of a decent SS one. Nor distortion, for that matter.
: --
: Trevor Wilson
: www.rageaudio.com.au
:
And this is 'proof' of, what ??
a) you are an incompetent tube pre-amp designer
b) again, logic fallacy at work @ Trev.Au - becoming quite a habit, eh, Trev.
?

Rudy

"Trevor Wilson" wrote in message : **Yep.
CJ proved that, with the Prem 16. ARC did not manage it with either
: the SP-11 or the SP-15. CJ went one step further and alleviated the problem
: of microphonics, which afflicts ALL tube preamps. ##
:
: --
: Trevor Wilson
: www.rageaudio.com.au
:
## got any proof for your 'opinion' ?
Rudy

"Ruud Broens" wrote in message

"Trevor Wilson" wrote in message
...
**Good for you. I've built a few tube preamps. None could approach
the S/N figures of a decent SS one. Nor distortion, for that matter.
--
Trevor Wilson
www.rageaudio.com.au

And this is 'proof' of, what ??
a) you are an incompetent tube pre-amp designer

I don't think Trevor would even try to design a tubed preamp. It would be
sorta like designing a new, improved buggy whip.

Arny Krueger wrote:
"Ruud Broens" wrote in message

"Trevor Wilson" wrote in message
...
**Good for you. I've built a few tube preamps. None could approach
the S/N figures of a decent SS one. Nor distortion, for that
matter.
--
Trevor Wilson
www.rageaudio.com.au

And this is 'proof' of, what ??
a) you are an incompetent tube pre-amp designer

I don't think Trevor would even try to design a tubed preamp. It
would be
sorta like designing a new, improved buggy whip.
Such a stupid analogy, such a stupid person making it.

Scott Wheeler

Personally I think non-DIYers should stick to solid state, as I think
you have to really enjoy tinkering to find tubes fun.

I agree buying Musical Fidelity products with parts-be they tubes or
otherwise-where the manufacturer tells you they have cornered the
market on the parts up front, is stupid. The Nuvistor was never favored
for audio work for good reasons when it was current, let alone now.
Nor have I ever been that thrilled with any ARC product.

However , as a general rule, making a tube box use a different tube
is usually pretty simple (not counting, yes, Nuvistors...) especially
if it's point to point wired. The only tube boxes I know where not
having the tube kills the box, aside from CRTs, is the GE Phasetron
which was used in FM exciters and RF generators.

To me, audio is like sex- doing it yourself is a lot more fun than
paying someone to do the job for you. It's like the old hams-unlike
today's fat lazy appliance operators, they used to say, if you've got
time to ham, you've got time to build.

"Ruud Broens" wrote in message
...

"Trevor Wilson" wrote in message
...
: **Good for you. I've built a few tube preamps. None could approach the
S/N
: figures of a decent SS one. Nor distortion, for that matter.
: --
: Trevor Wilson
: www.rageaudio.com.au
:
And this is 'proof' of, what ??

**Measurements,

a) you are an incompetent tube pre-amp designer

**Nope. Tubes are an inherently flawed technology.

b) again, logic fallacy at work @ Trev.Au - becoming quite a habit, eh,
Trev.

**Nope. I realise that English is not your first language, so I make
allowances.


--
Trevor Wilson
www.rageaudio.com.au

"Ruud Broens" wrote in message
...

"Trevor Wilson" wrote in message :
**Yep.
CJ proved that, with the Prem 16. ARC did not manage it with either
: the SP-11 or the SP-15. CJ went one step further and alleviated the
problem
: of microphonics, which afflicts ALL tube preamps. ##
:
: --
: Trevor Wilson
: www.rageaudio.com.au
:
## got any proof for your 'opinion' ?

**I didn't write any opinions. Just facts.


--
Trevor Wilson
www.rageaudio.com.au

"Trevor Wilson" wrote in message
...
:
: "Ruud Broens" wrote in message
: ...
:
: "Trevor Wilson" wrote in message :
: **Yep.
: CJ proved that, with the Prem 16. ARC did not manage it with either
: : the SP-11 or the SP-15. CJ went one step further and alleviated the
: problem
: : of microphonics, which afflicts ALL tube preamps. ##
: :
: : --
: : Trevor Wilson
: : www.rageaudio.com.au
: :
: ## got any proof for your 'opinion' ?
:
: **I didn't write any opinions. Just facts.
:
:
: --
: Trevor Wilson
: www.rageaudio.com.au
:
In that case: "the problem of microphonics, which afflicts ALL tube preamps"
Care to give a numeric example of this "problem", mr. Wilson ?:-)
Let's have some substance here, eh.
Rudy

"Trevor Wilson" wrote in message
...
:
: "Ruud Broens" wrote in message
: ...
:
: "Trevor Wilson" wrote in message
: ...
: : **Good for you. I've built a few tube preamps. None could approach the
: S/N
: : figures of a decent SS one. Nor distortion, for that matter.
: : --
: : Trevor Wilson
: : www.rageaudio.com.au
: :
: And this is 'proof' of, what ??
:
: **Measurements,

Let's have 'm, Trev what was the circuit used ? Measurement protocol ?

: a) you are an incompetent tube pre-amp designer
:
: **Nope. Tubes are an inherently flawed technology.

They can't be as inherently flawed as your reasoning, Trev.
:
: b) again, logic fallacy at work @ Trev.Au - becoming quite a habit, eh,
: Trev.
:
: **Nope. I realise that English is not your first language, so I make
: allowances.

Let's spell it out for ya: induction from one, 2, 3.. to ALL
is a nono, mr.TW still haven't figured that one out ?
tsktskWilson
: --
: Trevor Wilson
: www.rageaudio.com.au
:
:

"Ruud Broens" wrote in message
...

"Trevor Wilson" wrote in message
...
:
: "Ruud Broens" wrote in message
: ...
:
: "Trevor Wilson" wrote in message
: ...
: : **Good for you. I've built a few tube preamps. None could approach
the
: S/N
: : figures of a decent SS one. Nor distortion, for that matter.
: : --
: : Trevor Wilson
: : www.rageaudio.com.au
: :
: And this is 'proof' of, what ??
:
: **Measurements,

Let's have 'm, Trev what was the circuit used ? Measurement protocol ?

**I use several pieces of equipment. The centre piece is an ageing Sound
Technology 1700B. I use the suggested load and source impedances for each
device under test (usually 600 Ohms source and 10k load), all monitored with
Tek 465b 'scope. I also use a PC, sound card based system, when the mood
strikes me, but I'm an old fashioned kind of guy. I like 'proper' test
equipment. Some tests involve the use of a LinearX LMS (PC based) system.


: a) you are an incompetent tube pre-amp designer
:
: **Nope. Tubes are an inherently flawed technology.

They can't be as inherently flawed as your reasoning, Trev.

**OK then, show me YOUR test results of a tube preamp which offers a S/N
ratio of better than -100dB.

:
: b) again, logic fallacy at work @ Trev.Au - becoming quite a habit,
eh,
: Trev.
:
: **Nope. I realise that English is not your first language, so I make
: allowances.

Let's spell it out for ya: induction from one, 2, 3.. to ALL
is a nono, mr.TW still haven't figured that one out ?
tsktskWilson

**What the Hell are you on about?


--
Trevor Wilson
www.rageaudio.com.au

"Ruud Broens" wrote in message
...

"Trevor Wilson" wrote in message
...
:
: "Ruud Broens" wrote in message
: ...
:
: "Trevor Wilson" wrote in message :
: **Yep.
: CJ proved that, with the Prem 16. ARC did not manage it with either
: : the SP-11 or the SP-15. CJ went one step further and alleviated the
: problem
: : of microphonics, which afflicts ALL tube preamps. ##
: :
: : --
: : Trevor Wilson
: : www.rageaudio.com.au
: :
: ## got any proof for your 'opinion' ?
:
: **I didn't write any opinions. Just facts.
:
:
: --
: Trevor Wilson
: www.rageaudio.com.au
:
In that case: "the problem of microphonics, which afflicts ALL tube
preamps"
Care to give a numeric example of this "problem", mr. Wilson ?:-)
Let's have some substance here, eh.

**Impossible, since the problem varies from tube to tube and equipment to
equipment. That it exists, in not denied by any sane human in the audio
business. Do you deny that microphonics is an issue when suing tube
equipment?


--
Trevor Wilson
www.rageaudio.com.au