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Tube Amp with the "Good Kind of Distortion"

ShiZo

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Has there been a tube product reviewed yet that has been implemented correctly to have only the "good kind of distortion".
 

Jimbob54

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Has there been a tube product reviewed yet that has been implemented correctly to have only the "good kind of distortion".

You know what is coming next.....

You will need to define the distortion profile you are thinking of by "good". I suspect many that like that kind of thing have never seen the distortion profile their amp actually produces let alone point to what it is they like.
 

ahofer

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While not using tubes, I'd say Nelson Pass has devoted his career to designing amps with certain, apparently desirable, distortion profiles.
 
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ShiZo

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Is it even or odd order that's supposed to be "euphoric"?
 

MakeMineVinyl

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Is it even or odd order that's supposed to be "euphoric"?
Low order even harmonics are more directly musically related. Higher order harmonics have a much more complex relationship with the original signal. So if you have to have distortion, its better to have, in order of prominence, 2nd, 3rd, and 4th order. Balanced or push-pull circuits / outputs whether tube or solid state will eliminate the even order components and leave the odd order components. That's not an ideal situation, again if you have to have distortion.
 

NTK

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What about the inevitable inharmonic intermodulation distortions? Are they euphoric too?
 

MakeMineVinyl

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What about the inevitable inharmonic intermodulation distortions? Are they euphoric too?
No, they tend to be objectionable. However if an amplifier has relatively strong low order harmonic distortion relative to intermodulation distortion, the IM distortion will be covered up to a degree.
 

KenTajalli

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Distortion is distortion, how can it be good?
Any amp with high distortion is a bad amp.
but the reverse is not necessarily true.
it takes more than low distortion to make a good amp.
Tube amp, warm sound with good distortion is just bull.
 
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ShiZo

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Heroin is "euphoric." Tube amplifiers are euphonic (allegedly).
It's been 9 years since I did the first one, can confirm. Never tried the second :p
 

KenTajalli

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While not using tubes, I'd say Nelson Pass has devoted his career to designing amps with certain, apparently desirable, distortion profiles.
Can you please elaborate, I couldn't find anything about Pass desirable distortion on the net.
Thanx in advance
 

Gorgonzola

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Can you please elaborate, I couldn't find anything about Pass desirable distortion on the net.
Thanx in advance
Well, I think you'll search in vain for a Pass bald assertion that "distortion is desirable". However "distortion profile" is another matter.

There is Pass' rather famous article, "Audio distortion and feedback". There, for example, Pass says the following ...

"Many audiophiles believe that 2nd harmonic is to be preferred over 3rd harmonic. Certainly it is simpler in character, and it is well agreed that orders higher than third are more audible and less musical. However when given a choice between the sound of an amplifier whose characteristic is dominantly 2nd harmonic versus 3rd harmonic, a good percentage of listeners choose the 3rd.

"I have built many examples of simple 2nd and 3rd harmonic “types” of amplifiers over the last 35 years. When I say “types” I mean that they used simple Class A circuits described as “single-ended” versus “push-pull” and so tended to have a 2nd harmonic versus 3rd harmonic in the character of their distortion, but were not made to deliberately distort.

"Anecdotally, it appears that preferences break out roughly into a third of customers liking 2nd harmonic types, a third liking 3rd harmonic, and the remainder liking neither or both. Customers have also been known to change their mind over a period of time."


Reading the whole article it's apparent that Pass fairly explicitly advocates that a desirable distortion profile minimizes higher order harmonic distortion while tolerating substantial 2nd and/or 3rd order.
 

SIY

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Well, I think you'll search in vain for a Pass bald assertion that "distortion is desirable". However "distortion profile" is another matter.

There is Pass' rather famous article, "Audio distortion and feedback". There, for example, Pass says the following ...

"Many audiophiles believe that 2nd harmonic is to be preferred over 3rd harmonic. Certainly it is simpler in character, and it is well agreed that orders higher than third are more audible and less musical. However when given a choice between the sound of an amplifier whose characteristic is dominantly 2nd harmonic versus 3rd harmonic, a good percentage of listeners choose the 3rd.

"I have built many examples of simple 2nd and 3rd harmonic “types” of amplifiers over the last 35 years. When I say “types” I mean that they used simple Class A circuits described as “single-ended” versus “push-pull” and so tended to have a 2nd harmonic versus 3rd harmonic in the character of their distortion, but were not made to deliberately distort.

"Anecdotally, it appears that preferences break out roughly into a third of customers liking 2nd harmonic types, a third liking 3rd harmonic, and the remainder liking neither or both. Customers have also been known to change their mind over a period of time."


Reading the whole article it's apparent that Pass fairly explicitly advocates that a desirable distortion profile minimizes higher order harmonic distortion while tolerating substantial 2nd and/or 3rd order.
And there is actually zero data backing up his assertions. To Nelson's credit, he admits that the data aren't there and this is all conjecture and hearsay.

Ain't marketing wonderful?
 

Gorgonzola

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And there is actually zero data backing up his assertions. To Nelson's credit, he admits that the data aren't there and this is all conjecture and hearsay.

Ain't marketing wonderful?
Yada yada.

Conjecture & hearsay are the motivation for much scientific investigation.
 
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