[[email protected]]

"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued: http://easyurl.net/TubesTubes

[[email protected]]

On May 28, 11:03*am, wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued:http://easyurl.net/TubesTubes

I don't need my amp adding anything to the content. I just want to
hear what was recorded. The fatal flaw in your comment is
"generate". Why should the amp be generating content? A solid state
amp can pass any original harmonic content within human range that is
on the source just as well as a tube amp.

[Dave]

wrote in message
...
On May 28, 11:03 am, wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued:http://easyurl.net/TubesTubes

I don't need my amp adding anything to the content. I just want to
hear what was recorded. The fatal flaw in your comment is
"generate". Why should the amp be generating content? A solid state
amp can pass any original harmonic content within human range that is
on the source just as well as a tube amp.

Lots of folks like the "warm" tube sound. It's a personal preference, akin
to one's choice of speakers. Me, I like both, and have two systems, one
with a tubed amp and one with a solid state.

I will say that tubes sound better to me when being overdriven than solid
state... the distortion they produce seems to be less objectionable to my
subjective ears than that horrible SS noise. Not that that's a reason to
choose one over the other...

[[email protected]]

On May 28, 11:42*am, "Dave" wrote:
wrote in message

...
On May 28, 11:03 am, wrote:

"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued:http://easyurl.net/TubesTubes

I don't need my amp adding anything to the content. *I just want to
hear what was recorded. *The fatal flaw in your comment is
"generate". *Why should the amp be generating content? *A solid state
amp can pass any original harmonic content within human range that is
on the source just as well as a tube amp.

Lots of folks like the "warm" tube sound. *It's a personal preference, akin
to one's choice of speakers. *Me, I like both, and have two systems, one
with a tubed amp and one with a solid state.

I will say that tubes sound better to me when being overdriven than solid
state... the distortion they produce seems to be less objectionable to my
subjective ears than that horrible SS noise. *Not that that's a reason to
choose one over the other...

Warm? Can you quantify it? I think not.

The tube overdrive distortion is intentionally used sometimes by
electric guitar musicians. Someone decided to expand that and make it
a reason to prefer tube amps over solid state. If you're playing an
electric guitar then sure. But if you're playing recorded music then
no, do not overdrive your amp.

[Mr.T]

"Dave" wrote in message
news:z3f%j.232$i74.144@edtnps91...
I will say that tubes sound better to me when being overdriven than solid
state... the distortion they produce seems to be less objectionable to my
subjective ears than that horrible SS noise.

And of course a tube amp is likely to be overdriven, generally being of
relatively low power output, whereas a solid state amp should never need to
be overdriven in the first place, with large power outputs available at
relatively low cost. (or extremely low cost when compared to most tube
amps!)

MrT.

[JANA]

In actual fact a good vacuum tube amplifier does not add to the sound.
They are accurate, but there is a difference in the way the sound is
heard for a number of reasons.

The tube amplifier uses an output transformer. Some tube amplifiers also
use a driver transformer. Because of this, there is a lower slew rate.
Very high end output transformers will still have some effect on the
sound. The tube amplifier is higher in THD, but at odd harmonics. When
the tube amplifier is over driven, the clipping is not as harsh as on a
tube amplifier. These are the main reasons why musicians like tube
amplifier and say they sound better. Solid state amplifiers generally
have slightly less internal phase delay than tube amplifiers.

Solid state amplifiers generally have no output transformers or driver
transformers. Transistors and especially IC's in general have a faster
response than tubes. The slew rate on the solid state amplifier is much
faster, and it is possible to achieve lower distortion. Because of this,
the solid state amplifier is said to have a harsher sound. In actual
fact, a good solid state amplifier is very accurate compared to a tube
amplifier.

Basic description about slew rate:
http://en.wikipedia.org/wiki/Slew_rate

A more advanced explanation about slew rate:
http://www.engineering.uiowa.edu/~bm...wRateNotes.pdf

Tutorial About Slew Rate:
http://www.amplifier.cd/Tutorial/Slew_Rate/SlewRate.htm

Tube amplifiers also tend to have a lower damping factor than solid
state amplifiers. This will effect more of the accuracy or distortions
in the low frequency response. High damping factor will mean that there
is better compliance for controlling the speakers.

As for myself, my preference is a MOSFET amplifier. The performance
characteristics are much like a tube amplifier, except that it has the
slew rate and damping factor of the solid state amplifier.


--

JANA
_____


wrote in message
...
On May 28, 11:03 am, wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued:http://easyurl.net/TubesTubes

I don't need my amp adding anything to the content. I just want to
hear what was recorded. The fatal flaw in your comment is
"generate". Why should the amp be generating content? A solid state
amp can pass any original harmonic content within human range that is
on the source just as well as a tube amp.

[Trevor Wilson[_2_]]

"JANA" wrote in message
news
In actual fact a good vacuum tube amplifier does not add to the sound.
They are accurate, but there is a difference in the way the sound is
heard for a number of reasons.

The tube amplifier uses an output transformer.

**Most do. Some do not.

Some tube amplifiers also
use a driver transformer. Because of this, there is a lower slew rate.
Very high end output transformers will still have some effect on the
sound. The tube amplifier is higher in THD, but at odd harmonics.

**Not necessrily. It depends on the topology and what the designer intends.

When
the tube amplifier is over driven, the clipping is not as harsh as on a
tube amplifier.

**I presume you mean: "....not as harsh as on a transistor amplifier."
That statement is completely incorrect. It depends on the topology and what
the designer intends. Solid state amplifier can and have been designed to
clip 'gently'.

These are the main reasons why musicians like tube
amplifier and say they sound better.

**Nope. Musicians like SOME tube amps because they:
* May be designed to clip more gracefully than most SS designs.
* May be designed to possess enormous 'headroom'.
* Generally do not current limit in an unpleasant fashion (like SOME SS
designs).
* Have a name on the front which has good 'street cred'.

Solid state amplifiers generally
have slightly less internal phase delay than tube amplifiers.

**Huh?


Solid state amplifiers generally have no output transformers or driver
transformers.

**Usually, but there is no reason why they cannot be so manufactured. It's
just not necessary to do so.

Transistors and especially IC's in general have a faster
response than tubes.

**Absolute nonsense. And, moreover, the frequency response of the devices is
simply not an issue. It is (AGAIN!) the topology which dictates frequency
response.

The slew rate on the solid state amplifier is much
faster, and it is possible to achieve lower distortion.

**Nonsense.

Because of this,
the solid state amplifier is said to have a harsher sound.

**Nonsense. SOME SS amps sound harsher, due to poor implementation of
topology. The devices used are not the issue. How they're used, may well be.

In actual
fact, a good solid state amplifier is very accurate compared to a tube
amplifier.

**Usually, but not always.


Basic description about slew rate:
http://en.wikipedia.org/wiki/Slew_rate

A more advanced explanation about slew rate:
http://www.engineering.uiowa.edu/~bm...wRateNotes.pdf

Tutorial About Slew Rate:
http://www.amplifier.cd/Tutorial/Slew_Rate/SlewRate.htm

Tube amplifiers also tend to have a lower damping factor than solid
state amplifiers.

**Due to that pesky output transformer.

This will effect more of the accuracy or distortions
in the low frequency response. High damping factor will mean that there
is better compliance for controlling the speakers.

As for myself, my preference is a MOSFET amplifier. The performance
characteristics are much like a tube amplifier, except that it has the
slew rate and damping factor of the solid state amplifier.

**Your preference is duly noted. And discarded. MOSFETs deliver around ten
times the distortion of a good BJT or Triode. They are, unless operated at
significant Class A levels and/or with lots of global NFB, highly flawed
devices.


--
Trevor Wilson
www.rageaudio.com.au

[Arny Krueger]

"JANA" wrote in message
news
In actual fact a good vacuum tube amplifier does not add
to the sound. They are accurate,

Then we impose basic logic - all accurate amplifiers sound the same.

but there is a
difference in the way the sound is heard for a number of
reasons.

The differences come when the amplifiers are not accurate. This is borne out
by the discussion below:

The tube amplifier uses an output transformer. Some tube
amplifiers also use a driver transformer.

Some solid state amps used driver transformers. Interestingly enough, the
solid state amps that used driver transformers did not suffer many of the
faults of tubed amps that use output transformers.

Some solid state amps used output autotransformers, and again they did not
suffer many of the faults of tubed amps that use output transformers.

Because of this, there is a lower slew rate.

It appears that slew rate and rise time are being confused here. Output
transformers can impose a rise time limitation due to lack of high frequency
response. But this is not the same as a slew rate limitation. Slew rate
limiting imposes a lack of high frequency response that increases with
increasing signal level. A normal treble roll-off is independent of power
level. Treble roll-offs due to transformers are usually independent of power
level.

Very high end output
transformers will still have some effect on the sound.

It appears that tubed amplifiers with very good parts and designs can be
sonically accurate, similar to how good SS amps are. Therefore none of their
components will be having an effect on the sound. Either this statement
about output transformers still having some effect on the sound is
incorrect, or the author's opening statement that "...a good vacuum tube
amplifier does not add to the sound." is incorrect. I think he started out
right and went wrong.

The tube amplifier is higher in THD, but at odd
harmonics.

Just plain wrong. The balance of odd and even harmonics in an amplifier are
up to the designer. An amplifier with an unbalanced or single-ended design
will ultimately tend strongly towards producing even harmonics. An
amplifier with an balanced or push-pull design will ultimately tend strongly
towards producing odd harmonics because its basic design tends to cancel out
even harmonics. Tubes, transistors or whatever active device you might have,
these are very strong effects.

When the tube amplifier is over driven, the
clipping is not as harsh as on a tube amplifier.

Again, just plain wrong. The clipping behavior of an amplifier has a lot to
do with inverse feedback. The more inverse feedback, the sharper the
clipping. Back in the days when tubes were all we had, we could make very
nicely clipped square waves whenever we wanted to, using amplifiers that had
lots of inverse feedback.

A tubed amp with lots of inverse feedback will clip very nice and sharply.
And in fact, sharp clean clipping is the best alternative in most cases.
This is because sharp clipping yields the cleanest sound as long as you
don't clip the amp. With SS the ready alternative to sharp clipping is to
simply get a more power amplifier, or turn the volume down a little.

With gradual clipping, you have an amp that is a little dirty well below
maximum power. With sharp clipping you have an amp that is easier to get
clean sound out of - just turn it down a little.

These are the main reasons why musicians like tube amplifier
and say they sound better.

Musical instrument amps and high fidelity amps are two vastly different sets
of requirements. Anybody who tries to apply musical instrument technology to
high fidelity amps is badly confused.

Solid state amplifiers
generally have slightly less internal phase delay than
tube amplifiers.

Generally not true. When you look at solid state maps with no output
transformers and compare them to tubed amps with output transformers which
is the usual case, the SS amp's high frequency advantage comes primarily
from the absence of an output transformer. So its not the absence of tubes
that gives the SS amp its great potential for good high frequency response,
it is the absence of an output transformer. Most SS audio amps have high
frequency response that is intentionally rolled-off to avoid problems with
EMI, etc.

Solid state amplifiers generally have no output
transformers or driver transformers.

Agreed, and the major benefit comes from getting rid of the OPT. However,
tubed amps that lack OPTs have been built and other than parts count and
attendant reliability problems, they can be very good, but at a high price.

Transistors and
especially IC's in general have a faster response than
tubes.

That's why UHF TV stations have tubed RF amplifiers. In the audio range, the
best estimate is that either tubes or transistors as devices have more than
enough high frequency response and are fast enough.

The slew rate on the solid state amplifier is much
faster, and it is possible to achieve lower distortion.

Two irrelevant clauses tied together to make up a misconception. Slew rate
isn't a problem with tubes, after all we had tubed oscilloscopes that
produced very nice square waves up into the MHz. In power amps the limit to
high frequency response is the OPT. But even with OPTs, a very good OPT does
not limit the HF response of the amp in a way that is necessarily audible.

SS amps are easier to build with low distortion because of the well-known
trade-off between gain and distortion. The usual methodology for building a
low distortion amplifier, whether tubed or SS, is to build a very good low
distortion, high gain amplifier, and trade off the gain for low distortion
with loop feedback. It's simply cheaper and easier to build good high gain
amplifiers with SS than tubes. Thus, SS amps more commonly have very low
distortion.

Because of this, the solid state amplifier is said to
have a harsher sound.

What sort of bass-ackwards logic equates harsher sound with low distortion?
This is just plain nuts.

In actual fact, a good solid state
amplifier is very accurate compared to a tube amplifier.

Both tubed and SS amplifiers can be built that are sonically accurate. IOW,
you have a SS amp and a tubed amp that are each very accurate and
good-sounding, and impossible to distinguish based on their Sonics. Thing
is, the good-sounding SS amp can easily to be a very practical thing, and
readily available. The tubed amp is going to be larger, heavier, less
reliable, and far more expensive.

The silliness is obsessing over amplifiers. Amplifiers are a solved problem.
The problem is speakers and rooms. The best use of amplifier technology is
to trade it off for better sounding speakers and rooms.

[[email protected]]

On Jun 1, 5:34 am, "Arny Krueger" wrote:
"JANA" wrote in message

news
In actual fact a good vacuum tube amplifier does not add
to the sound. They are accurate,

Then we impose basic logic - all accurate amplifiers sound the same.

but there is a
difference in the way the sound is heard for a number of
reasons.

The differences come when the amplifiers are not accurate. This is borne out
by the discussion below:

The tube amplifier uses an output transformer. Some tube
amplifiers also use a driver transformer.

Some solid state amps used driver transformers. Interestingly enough, the
solid state amps that used driver transformers did not suffer many of the
faults of tubed amps that use output transformers.

Some solid state amps used output autotransformers, and again they did not
suffer many of the faults of tubed amps that use output transformers.

SS amps sometimes used full OPTs and they had the same problems.
Altec's SS models using a 28 volt battery for standby power did. They
do not like to be run into an open load either. But, they make
surprisingly good guitar amps when used with a good tube pre. See
below.


Because of this, there is a lower slew rate.

It appears that slew rate and rise time are being confused here. Output
transformers can impose a rise time limitation due to lack of high frequency
response. But this is not the same as a slew rate limitation. Slew rate
limiting imposes a lack of high frequency response that increases with
increasing signal level. A normal treble roll-off is independent of power
level. Treble roll-offs due to transformers are usually independent of power
level.

When the tube amplifier is over driven, the
clipping is not as harsh as on a tube amplifier.

Again, just plain wrong. The clipping behavior of an amplifier has a lot to
do with inverse feedback. The more inverse feedback, the sharper the
clipping. Back in the days when tubes were all we had, we could make very
nicely clipped square waves whenever we wanted to, using amplifiers that had
lots of inverse feedback.

The OPT fortunately inhibits the sharpness of clipping in most tube
amps. Tube amp clipping is much less likely to tear up tweeters than
is solid state amp clipping. You don't have the smoked tweeters from
underpowered amp clipping with 30-100 watt tube amps you do with
100-200 watt SS amps on many very inefficient speakers today even
though the tube amps clip more than the solid state ones do. many
home speaker tweeters have a demonstrated sustained square wave power
handling capacity of nil.

A tubed amp with lots of inverse feedback will clip very nice and sharply.
And in fact, sharp clean clipping is the best alternative in most cases.
This is because sharp clipping yields the cleanest sound as long as you
don't clip the amp. With SS the ready alternative to sharp clipping is to
simply get a more power amplifier, or turn the volume down a little.

With gradual clipping, you have an amp that is a little dirty well below
maximum power. With sharp clipping you have an amp that is easier to get
clean sound out of - just turn it down a little.

These are the main reasons why musicians like tube amplifier
and say they sound better.

Musical instrument amps and high fidelity amps are two vastly different sets
of requirements. Anybody who tries to apply musical instrument technology to
high fidelity amps is badly confused.


Substitute "electric guitar amplifiers for use by rock players (and
others wanting a rockish sound) " for "musical instrument amplifier"
and yoou have a correct statement. Acoustic guitar, steel guitar, and
many bass guitar applications as well as most keyboard and other
combo amp users want amplification without modification. Hi fi
amplifiers or PA amplifiers work best for this except for form factor.

[Arny Krueger]

wrote in message

On Jun 1, 5:34 am, "Arny Krueger"
wrote:
"JANA" wrote in message

When the tube amplifier is over driven, the
clipping is not as harsh as on a tube amplifier.

Again, just plain wrong. The clipping behavior of an
amplifier has a lot to do with inverse feedback. The
more inverse feedback, the sharper the clipping. Back in
the days when tubes were all we had, we could make very
nicely clipped square waves whenever we wanted to, using
amplifiers that had lots of inverse feedback.

The OPT fortunately inhibits the sharpness of clipping in
most tube amps.

I doubt that a casual glance at a scope trace would allow most people to
sort SS and tubed amps. In fact most good tubed amps produce very nice
sharp-edged square waves.

Tube amp clipping is much less likely to
tear up tweeters than is solid state amp clipping.

That whole line of thinking - that clipping necessarily add high frequency
information to music, has been debunked many times.

You
don't have the smoked tweeters from underpowered amp
clipping with 30-100 watt tube amps you do with 100-200
watt SS amps on many very inefficient speakers today even
though the tube amps clip more than the solid state ones
do.

The reason for that has nothing to do with tubes versus transistors. The
first order effect is that a 200 wpc amp has more than 6 times more power
than a 30 wpc amp. The first order effect predominates.

many home speaker tweeters have a demonstrated
sustained square wave power handling capacity of nil.

That would be a problem for speaker designers to solve. The good news is
that the problem has been solved many times.

[Mr.T]

wrote in message
...
many home speaker tweeters have a demonstrated sustained square wave
power handling capacity of nil.

What a completely unqualified, nonsensical statement!

MrT.

[Norman M. Schwartz]

JANA wrote:
In actual fact a good vacuum tube amplifier does not add to the sound.
They are accurate, but there is a difference in the way the sound is
heard for a number of reasons.


How can they be 'accurate? Tubes from different manufacturers as well as
different dates of manufacture from the same manufacturer all claim to sound
different from one another?

[Clyde Slick]

On 1 Iun, 16:48, "Norman M. Schwartz" wrote:
JANA wrote:
In actual fact a good vacuum tube amplifier does not add to the sound.
They are accurate, but there is a difference in the way the sound is
heard for a number of reasons.

How can they be 'accurate? Tubes from different manufacturers as well as
different dates of manufacture from the same manufacturer all claim to sound
different from one another?



You are finally getting it.
Accur\rcy is your chimera
recorded music is a produced stew,
not necessarily a depiction of any particular real musical event,
and even when it is intended to be so it usually is still a
sausage processed through a pipeline of processing.

There is no "Exact" depiction of what is is supposed to sound like.
If you REALLY want to be accurate, in some
limitede sense of the word, you will have to listen
to it with the same monitoring system in the same room
in which the producer listens to his sausage, I mean recording.

[Arny Krueger]

"Norman M. Schwartz" wrote in message

JANA wrote:

In actual fact a good vacuum tube amplifier does not add
to the sound. They are accurate, but there is a
difference in the way the sound is heard for a number of
reasons.

How can they be 'accurate? Tubes from different
manufacturers as well as different dates of manufacture
from the same manufacturer all claim to sound different
from one another?

Good question. Of course many of the claims that tubes from different
manufacturers as well as different dates of manufacture
from the same manufacturer sound differentfrom one another are the expected
results of sighted evaluations.

[Mr.T]

"JANA" wrote in message
news
In actual fact a good vacuum tube amplifier does not add to the sound.
They are accurate, but there is a difference in the way the sound is
heard for a number of reasons.
snip

.... Then goes on to contradict himself and explain why many tube amplifiers
might NOT in fact be accurate!
(some of which is actually true)

Having a bet either way? Or simply pointing out (not very clearly), that
most valve amps are not in fact accurate and therefore not to be considered
"GOOD vacuum tube amplifiers" by most people?

MrT.

[Ian Thompson-Bell]

wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued: http://easyurl.net/TubesTubes


There is a lot missing from this article. First, it is triodes alone
that generate pleasing 2nd harmonic distortion. Pentodes generate odd
harmonics just as much as transistors do.

Second the amount of distortion is level dependent. The output stages of
an amp create by far the most distortion. Any push pull amp output stage
will, by definition cancel most of the even order harmonics and leave
many nasty odd harmonics in the output - no better in that respect than
a transistor amp.

So, the ONLY power amp with mainly odd harmonics in its output will be a
triode SET.

Cheers

Ian

[Arny Krueger]

"Ian Thompson-Bell" wrote in
message
wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the
device can pass or generate..."

Continued: http://easyurl.net/TubesTubes


There is a lot missing from this article. First, it is
triodes alone that generate pleasing 2nd harmonic
distortion. Pentodes generate odd harmonics just as much
as transistors do.

It is a myth that triodes generate only even harmonics. In fact, tubes have
basically exponential response, which leads to the generation of a wide
variety of orders of distortion, both odd and even.

[Ian Thompson-Bell]

Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the
device can pass or generate..."

Continued: http://easyurl.net/TubesTubes

There is a lot missing from this article. First, it is
triodes alone that generate pleasing 2nd harmonic
distortion. Pentodes generate odd harmonics just as much
as transistors do.

It is a myth that triodes generate only even harmonics. In fact, tubes have
basically exponential response, which leads to the generation of a wide
variety of orders of distortion, both odd and even.



No, pentodes have an exponential transfer function like BJTs do, but
triodes have a simpler ^3/2 transfer function which produces a different
harmonic content.

Cheers

Ian

[Arny Krueger]

"Ian Thompson-Bell" wrote in
message
Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the
device can pass or generate..."

Continued: http://easyurl.net/TubesTubes

There is a lot missing from this article. First, it is
triodes alone that generate pleasing 2nd harmonic
distortion. Pentodes generate odd harmonics just as much
as transistors do.

It is a myth that triodes generate only even harmonics.
In fact, tubes have basically exponential response,
which leads to the generation of a wide variety of
orders of distortion, both odd and even.

No, pentodes have an exponential transfer function like
BJTs do, but triodes have a simpler ^3/2 transfer
function which produces a different harmonic content.

In my book, what you call ^3/2 transfer function is just another flavor of
exponential.

A ^3/2 transfer function can be read as the square root of cubed, which is
nothing like pure even order or pure second order.

[Ian Thompson-Bell]

Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the
device can pass or generate..."

Continued: http://easyurl.net/TubesTubes
There is a lot missing from this article. First, it is
triodes alone that generate pleasing 2nd harmonic
distortion. Pentodes generate odd harmonics just as much
as transistors do.
It is a myth that triodes generate only even harmonics.
In fact, tubes have basically exponential response,
which leads to the generation of a wide variety of
orders of distortion, both odd and even.

No, pentodes have an exponential transfer function like
BJTs do, but triodes have a simpler ^3/2 transfer
function which produces a different harmonic content.

In my book, what you call ^3/2 transfer function is just another flavor of
exponential.


I sujggest you get a better book.

A ^3/2 transfer function can be read as the square root of cubed, which is
nothing like pure even order or pure second order.


A simple expansion shows that the even order terms dominate. See any
book on tubes for details.

Cheers

Ian

[Trevor Wilson[_2_]]

"Ian Thompson-Bell" wrote in message
...
wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued: http://easyurl.net/TubesTubes


There is a lot missing from this article. First, it is triodes alone that
generate pleasing 2nd harmonic distortion. Pentodes generate odd harmonics
just as much as transistors do.

**So much nonsense, so little time to correct it. Why this myth continues to
be perpetrated is a complete mystery. The TOPOLOGY dictates what type of
harmonics are generated, not the devices. Push pull eliminates even order
distortion products. Valve or solid state.


Second the amount of distortion is level dependent. The output stages of
an amp create by far the most distortion. Any push pull amp output stage
will, by definition cancel most of the even order harmonics and leave many
nasty odd harmonics in the output - no better in that respect than a
transistor amp.

**Nonsense.


So, the ONLY power amp with mainly odd harmonics in its output will be a
triode SET.

**Nonsense. Where you do you get this nonsense from?


--
Trevor Wilson
www.rageaudio.com.au

[Trevor Wilson[_2_]]

"flipper" wrote in message
...
On Thu, 29 May 2008 09:01:52 +1000, "Trevor Wilson"
wrote:



"Ian Thompson-Bell" wrote in message
...
wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued: http://easyurl.net/TubesTubes


There is a lot missing from this article. First, it is triodes alone
that
generate pleasing 2nd harmonic distortion. Pentodes generate odd
harmonics
just as much as transistors do.

**So much nonsense, so little time to correct it. Why this myth continues
to
be perpetrated is a complete mystery. The TOPOLOGY dictates what type of
harmonics are generated, not the devices.

Well, you're half right. They both dictate the harmonics.

**I am 100% correct. Topology is the factor. Not the devices. Of course,
various devices DO contribute different distortion amounts. For instance:

* At low bias currents, pentodes add large amounts of distortion.
* At low bias current, triodes add smaller amounts of distortion.
* At low bias currents, MOSFETs add very large amounts of distortion.
* At low bias currents, BJTs add smaller amounts of distortion.


Push pull eliminates even order
distortion products. Valve or solid state.

But does nothing for the odd orders, which are dictated by the
devices.

**Sure. ALL amplifiying devices add odd order distortion. At moderate bias
currents, the approximate order is (from best to worst):

BJTs
Triodes
Pentodes
MOSFETs

At high bias currents, the order shifts somewhat to:

BJTs
MOSFETs
Triodes
Pentodes

It is the TOPOLOGY which dominates the issue of distortion production,
however. Depending on the amount of feedback employed, the devices used
makes little difference.

--
Trevor Wilson
www.rageaudio.com.au

[Trevor Wilson[_2_]]

"flipper" wrote in message
...
On Thu, 29 May 2008 09:56:14 +1000, "Trevor Wilson"
wrote:



"flipper" wrote in message
. ..
On Thu, 29 May 2008 09:01:52 +1000, "Trevor Wilson"
wrote:



"Ian Thompson-Bell" wrote in message
...
wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can
pass
or generate..."

Continued: http://easyurl.net/TubesTubes


There is a lot missing from this article. First, it is triodes alone
that
generate pleasing 2nd harmonic distortion. Pentodes generate odd
harmonics
just as much as transistors do.

**So much nonsense, so little time to correct it. Why this myth
continues
to
be perpetrated is a complete mystery. The TOPOLOGY dictates what type
of
harmonics are generated, not the devices.

Well, you're half right. They both dictate the harmonics.

**I am 100% correct.

No, you're not.

Topology is the factor.

It's one factor.

**It is, by far, the major factor. It swamps any influences by the output
devices. Take away global NFB, for instance, and differences between devices
is more readily apparent.


Not the devices.

B.S.

**Keep dissagreeing all you wish. You'll still be wrong.


Of course,
various devices DO contribute different distortion amounts.

And different harmonic distributions as well.

**All of which is swamped by topology differences.



For instance:

* At low bias currents, pentodes add large amounts of distortion.
* At low bias current, triodes add smaller amounts of distortion.
* At low bias currents, MOSFETs add very large amounts of distortion.
* At low bias currents, BJTs add smaller amounts of distortion.


Push pull eliminates even order
distortion products. Valve or solid state.

But does nothing for the odd orders, which are dictated by the
devices.

**Sure. ALL amplifiying devices add odd order distortion.

Yes, but with different distributions.

**All of which is swamped by different topologies.


At moderate bias
currents, the approximate order is (from best to worst):

BJTs
Triodes
Pentodes
MOSFETs

At high bias currents, the order shifts somewhat to:

BJTs
MOSFETs
Triodes
Pentodes

Except for BJTs being the worst of the lot under all conditions that's
not too terribly screwed up.

**Wrong. Modern BJTs are, by far, the most linear output devices available.
Look at the Hfe vs. Ic curve of this device:

http://www.datasheetcatalog.org/data...shiba/3228.pdf

A VERY linear (low distortion) device over a very wide range of currents.
It's PNP complement is similarly low distortion.



It is the TOPOLOGY which dominates the issue of distortion production,
however.

Wrong.

**Don't be silly. Compare SE to PP. Compare zero global NFB to high global
NFB topologies.


Depending on the amount of feedback employed, the devices used
makes little difference.

Also wrong.

**Here's where I get to say: PROVE IT.


--
Trevor Wilson
www.rageaudio.com.au

[Arny Krueger]

"flipper" wrote in message

On Thu, 29 May 2008 09:56:14 +1000, "Trevor Wilson"
wrote:



"flipper" wrote in message
...
On Thu, 29 May 2008 09:01:52 +1000, "Trevor Wilson"
wrote:



"Ian Thompson-Bell" wrote in
message ...
wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that
the device can pass or generate..."

Continued: http://easyurl.net/TubesTubes


There is a lot missing from this article. First, it
is triodes alone that
generate pleasing 2nd harmonic distortion. Pentodes
generate odd harmonics
just as much as transistors do.

**So much nonsense, so little time to correct it. Why
this myth continues to
be perpetrated is a complete mystery. The TOPOLOGY
dictates what type of harmonics are generated, not the
devices.

Well, you're half right. They both dictate the
harmonics.

**I am 100% correct.

No, you're not.

Topology is the factor.

It's one factor.

Not the devices.

B.S.

Of course,
various devices DO contribute different distortion
amounts.

And different harmonic distributions as well.

For instance:

* At low bias currents, pentodes add large amounts of
distortion.
* At low bias current, triodes add smaller amounts of
distortion.
* At low bias currents, MOSFETs add very large amounts
of distortion.
* At low bias currents, BJTs add smaller amounts of
distortion.


Push pull eliminates even order
distortion products. Valve or solid state.

But does nothing for the odd orders, which are dictated
by the devices.

**Sure. ALL amplifying devices add odd order distortion.

Yes, but with different distributions.

So what?

With SS amps we don't have as much problem with phase shift inside the loop
hindering the proper use of loop feedback. It is far more economically
feasible to have large open loop gain. Thus despite all the intuitively
attractive but completely wrong-headed hand-waving arguments against loop
feedback, SS amps are able to use more of it. The net result is that SS amps
are far more linear, particularly at the ends of the audible range.

We've already had one tubie admit that even the best tubed amps make very
suboptimal subwoofer amps. Less-expensive tubes amps such as the classic
Dyna 70 and the amplifier sections of the better tubed receivers start
crapping out below 100 Hz which is well into the normal audible range for
even bookshelf speakers.


At moderate bias
currents, the approximate order is (from best to worst):

BJTs
Triodes
Pentodes
MOSFETs

At high bias currents, the order shifts somewhat to:

BJTs
MOSFETs
Triodes
Pentodes

Except for BJTs being the worst of the lot under all
conditions that's not too terribly screwed up.

It doesn't matter. Device linearity doesn't matter nearly as much as the
final performance of the finished product. One of the strong advantages of
SS is the ability to economically cascade stages to get higher open-loop
gain with low enough phase shift to provide superior stability margins at
all relevant frequencies.

It is the TOPOLOGY which dominates the issue of
distortion production, however.

Wrong.

Just saying it without supporting evidence is just meaningless posturing.

Depending on the amount of feedback employed, the
devices used
makes little difference.

Also wrong.

Just saying it without supporting evidence is just meaningless posturing.

[dizzy]

Arny Krueger wrote:

We've already had one tubie admit that even the best tubed amps make very
suboptimal subwoofer amps.

Whoa!

Wouldn't that be something along the lines of "even the best putters
make very sub-optimal drivers"?

[Arny Krueger]

"Ian Thompson-Bell" wrote in
message
wrote:

So, the ONLY power amp with mainly odd harmonics in its
output will be a triode SET.

No, if you want mainly odd harmonics, you do something symmetrical, like
push-pull.

[Ian Thompson-Bell]

Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
wrote:

So, the ONLY power amp with mainly odd harmonics in its
output will be a triode SET.

No, if you want mainly odd harmonics, you do something symmetrical, like
push-pull.



NO, PP CANCELS odd harmonics.

Cheers

[Arny Krueger]

"Ian Thompson-Bell" wrote in
message
Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
wrote:

So, the ONLY power amp with mainly odd harmonics in its
output will be a triode SET.

No, if you want mainly odd harmonics, you do something
symmetrical, like push-pull.


NO, PP CANCELS odd harmonics.

A totally false statement that any second-year engineering student would
recognize as being false.

[Ian Thompson-Bell]

Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
wrote:

So, the ONLY power amp with mainly odd harmonics in its
output will be a triode SET.

No, if you want mainly odd harmonics, you do something symmetrical, like
push-pull.



Sorry, I meant even harmonics and my prior reply to this post was BS.

CHeers

Ian

[Arny Krueger]

"Ian Thompson-Bell" wrote in
message
Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
wrote:

So, the ONLY power amp with mainly odd harmonics in its
output will be a triode SET.

No, if you want mainly odd harmonics, you do something
symmetrical, like push-pull.



Sorry, I meant even harmonics and my prior reply to this
post was BS.

Well, now having corrected yourself - deal with the issue that I raised.

[Ian Thompson-Bell]

Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
Arny Krueger wrote:
"Ian Thompson-Bell" wrote in
message
wrote:
So, the ONLY power amp with mainly odd harmonics in its
output will be a triode SET.
No, if you want mainly odd harmonics, you do something
symmetrical, like push-pull.


Sorry, I meant even harmonics and my prior reply to this
post was BS.

Well, now having corrected yourself - deal with the issue that I raised.




Which was?

Cheers

Ian

[Patrick Turner]

Ian Thompson-Bell wrote:

wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued: http://easyurl.net/TubesTubes

There is a lot missing from this article. First, it is triodes alone
that generate pleasing 2nd harmonic distortion. Pentodes generate odd
harmonics just as much as transistors do.

Second the amount of distortion is level dependent. The output stages of
an amp create by far the most distortion. Any push pull amp output stage
will, by definition cancel most of the even order harmonics and leave
many nasty odd harmonics in the output - no better in that respect than
a transistor amp.

Yes, but the PP tube amp can easily have 0.03% THD at 1 watt levels
for excellent listening where THD/IMD is below audibility.

So how then is the distortion responsible for the different sound of an
amp?


So, the ONLY power amp with mainly odd harmonics in its output will be a
triode SET.

Your'e wrong, SE triode amps have THD comprising nearly all 2H almost up
to clipping.

3H, 5H, 7H, 9H are at extremely low levels at ordinary listening levels.

The kind of IMD produced in amplifiers is MUCH more important than the
THD itself.

The IMD produced in an SET is more benign than that produced in an amp
with a similar quantity of 3H, which would have to be a PP amp.

And don't forget, the amount of distortion is NFB dependant as well as
level dependant, and cancellation dependant.
And the PSU filtering needs to be good for good sound,
and the amount of class A needs to be high.....

Patrick Turner.




Cheers

Ian

[Ian Thompson-Bell]

flipper wrote:
On Wed, 28 May 2008 17:34:05 +0100, Ian Thompson-Bell
wrote:

wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued: http://easyurl.net/TubesTubes

There is a lot missing from this article.

Yes, as well as full of 'opinion'. There's not a single measurement in
it.

First, it is triodes alone
that generate pleasing 2nd harmonic distortion.

No, you're confusing SE with PP.


No, I was being inaccurate! I should have said triodes generate a larger
proportion of second harmonic compared to higher ones than either
pentodes of BJTs.

Pentodes generate odd
harmonics just as much as transistors do.

No and it's misleading to speak of simply 'odd' harmonics. It's the
higher order harmonics that are harsh and then there's the issue of
the harmonic mix.

Hmm, the ratio of 3rd (and higher odd harmonics) to 2nd harmonic
distortion in pentodes is greater than in triodes because of the
different transfer function.


All of which smacks a bit of voo-doo because, according to
measurements, they're all below 'audible' and so, in theory, should be
of no consequence. But then, and again according to measurements, THD
that's 'inaudible' (or at least unoffensive) in a tube amp offends
like nails on a blackboard in SS amps so an SS amp *must* have lower
THD figures to be tolerable.


The danger here of course is that measuring THD alone is not sufficient.

Second the amount of distortion is level dependent. The output stages of
an amp create by far the most distortion. Any push pull amp output stage
will, by definition cancel most of the even order harmonics

Which includes triodes.

Indeed.


and leave
many nasty odd harmonics in the output - no better in that respect than
a transistor amp.

No.

Which bit is not correct the whole or just the latter part?


So, the ONLY power amp with mainly odd harmonics in its output will be a
triode SET.

Judging from the rest you apparently mean "even harmonics" but what
does "mainly" mean?

Yes, mixing my odds and evens again.


Cheers

Ian

[Peter Wieck]

On May 28, 11:03*am, wrote:
"In a word: YES...

"The answer is rooted in the harmonic content that the device can pass
or generate..."

Continued:http://easyurl.net/TubesTubes

Um, this is a troll. And firmly rooted in received wisdom and blind
faith.

As such, no opinions will be made or changed by it, it serves no
useful purpose, and comment upon it merely gives the Original Poster
the attention he/she wants anyway.

Those who prefer tubes will continue to prefer them. Those who enjoy
tubes as another aspect of the Audio Hobby will continue to do so...
and so forth.

Peter Wieck
Melrose Park, PA

[Arny Krueger]

wrote in message


"In a word: YES...

"The answer is rooted in the harmonic content that the
device can pass or generate..."

There is no question that tubed power amps are inferior when it comes to
passing harmonic content. They are just too nonlinear and just too limited
in terms of power bandwidth to compare with more modern alternatives.

As far as the generation of harmonic content goes, it is unclear why
maximizing harmonic content would even be desirable in a component of a high
fidelity system. Furthermore, if versatile and powerful harmonic content
generation were desired, then the tools of choice would be from the digital
domain.

[RapidRonnie]

On May 28, 2:08 pm, "Arny Krueger" wrote:
wrote in message



"In a word: YES...
"The answer is rooted in the harmonic content that the
device can pass or generate..."

There is no question that tubed power amps are inferior when it comes to
passing harmonic content. They are just too nonlinear and just too limited
in terms of power bandwidth to compare with more modern alternatives.

As far as the generation of harmonic content goes, it is unclear why
maximizing harmonic content would even be desirable in a component of a high
fidelity system. Furthermore, if versatile and powerful harmonic content
generation were desired, then the tools of choice would be from the digital
domain.

Properly designed tube amplifiers have entirely satisfactory bandpass
and distortion characteristics. Passing frequencies above 35-50 kHz is
very undesireable in an audio amplifier. Ideally a shallow taper from
about 25 kHz and a drop at 50 or so is desireable.

Many solid state audio amplifiers work well for RF in the 100-300 kHz
range. That is not a feature, it's a bug. The output transformer of a
tube amplifier beneficially throttles this extreme HF response.

[Arny Krueger]

"RapidRonnie" wrote in message

On May 28, 2:08 pm, "Arny Krueger"
wrote:
wrote in message



"In a word: YES...
"The answer is rooted in the harmonic content that the
device can pass or generate..."

There is no question that tubed power amps are inferior
when it comes to passing harmonic content. They are
just too nonlinear and just too limited in terms of
power bandwidth to compare with more modern
alternatives.

As far as the generation of harmonic content goes, it is
unclear why maximizing harmonic content would even be
desirable in a component of a high fidelity system.
Furthermore, if versatile and powerful harmonic content
generation were desired, then the tools of choice would
be from the digital domain.

Properly designed tube amplifiers have entirely
satisfactory bandpass and distortion characteristics.

Well, if you say that for a far higher price and considerably greater
inconvenience, it is possible to have a tubed amp with good performance, I'd
have to agree.


Passing frequencies above 35-50 kHz is very undesireable
in an audio amplifier. Ideally a shallow taper from about
25 kHz and a drop at 50 or so is desirable.

If you include the effects of real-world speaker loads, most tubed amps have
audible issues inside the 20-20 kHz range because of their far higher source
impedance.

Good thing you have nothing to say about the low bad performance of tubed
amps, because all but the really expensive and heavy ones do rather more
poorly in the bass.


Many solid state audio amplifiers work well for RF in the
100-300 kHz range.

That's not typical. Everybody knows that ultrasonic response is an open door
for problems with EMI, etc. Most SS amps have artificially sacrificed high
frequency response to enhance their usability.

That is not a feature, it's a bug. The
output transformer of a tube amplifier beneficially throttles this extreme
HF response.

Throttling the HF response of a SS amp only takes one or two penny-cost
capacitors.

But I will give the majority of tubed amps a nod of sorts for their inferior
power bandwidth below 30 Hz.

[RapidRonnie]

If you include the effects of real-world speaker loads, most tubed amps have
audible issues inside the 20-20 kHz range because of their far higher source
impedance.

Good thing you have nothing to say about the low bad performance of tubed
amps, because all but the really expensive and heavy ones do rather more
poorly in the bass.

All tube amps are expensive and heavy these days. No one is
advocating them for subwoofer drivers.

Any good push pull 6L6 or 6550 power amp will drive a classic
Klipsch, Altec or JBL setup to higher bass SPLs than any normal person
can tolerate. Headbangers wanting more should move out of town so as
not to disturb the rest of us.

[jamesgangnc]

"RapidRonnie" wrote in message
...


If you include the effects of real-world speaker loads, most tubed amps
have
audible issues inside the 20-20 kHz range because of their far higher
source
impedance.

Good thing you have nothing to say about the low bad performance of tubed
amps, because all but the really expensive and heavy ones do rather more
poorly in the bass.

All tube amps are expensive and heavy these days. No one is
advocating them for subwoofer drivers.

Any good push pull 6L6 or 6550 power amp will drive a classic
Klipsch, Altec or JBL setup to higher bass SPLs than any normal person
can tolerate. Headbangers wanting more should move out of town so as
not to disturb the rest of us.

Tubes are inherently bad devices to drive a low impedance load where as
solid state is perfectly happy being coupled directly to a speaker. You
can't make a tube current amp and that's what you need for audio.

[Trevor Wilson[_2_]]

"RapidRonnie" wrote in message
...
On May 28, 2:08 pm, "Arny Krueger" wrote:
wrote in message



"In a word: YES...
"The answer is rooted in the harmonic content that the
device can pass or generate..."

There is no question that tubed power amps are inferior when it comes to
passing harmonic content. They are just too nonlinear and just too
limited
in terms of power bandwidth to compare with more modern alternatives.

As far as the generation of harmonic content goes, it is unclear why
maximizing harmonic content would even be desirable in a component of a
high
fidelity system. Furthermore, if versatile and powerful harmonic content
generation were desired, then the tools of choice would be from the
digital
domain.

Properly designed tube amplifiers have entirely satisfactory bandpass
and distortion characteristics. Passing frequencies above 35-50 kHz is
very undesireable in an audio amplifier. Ideally a shallow taper from
about 25 kHz and a drop at 50 or so is desireable.

**Bull****. Such a poor frequency response, will lead to a severely and
audibly compromised phase response. The human ear is very sensitive to phase
problems. A linear frequency response, which leads to a close to 0 degree
phase shift at 20kHz is desirable.


Many solid state audio amplifiers work well for RF in the 100-300 kHz
range. That is not a feature, it's a bug. The output transformer of a
tube amplifier beneficially throttles this extreme HF response.

**Bull****. The output transformer damages the frequency response of valve
amps. Valves are inherently high frequency devices.


--
Trevor Wilson
www.rageaudio.com.au