Tube vs Transistor Amps...They sound different... its a fact.

[escksu]

Tube amps sound different from solid state amps. Its not about better or worse, its about a difference. For those who thought that they sound same as solid state amps, well, I have to say they are all wrong.

This video from audioholics is a great one and provides the key reasons why they sound different. One of the main reason is distortion. Its measurable.

 

[kn0ppers]

I don't think anybody claimed they sounded identical?!

 

[Sgt. Ear Ache]

strawman

 

[Zensō]

Of course they sound different if they measure differently. The question is whether they sound different if they measure the same.

EDIT: Of course they sound different if they measure differently within the audible limits.

 

[danadam]

Of course they sound different if they measure differently.

Somewhat strong statement. "They may sound different if they measure differently" would be more correct.

 

[KeithPhantom]

Of course they sound different if they measure differently. The question is whether they sound different if they measure the same.

They cannot sound different if they measure exactly the same if we're assuming complete absolutism and objectivism. They will be able to output the same waveforms at exactly the same amplified with the same distortion profile.

 

[KeithPhantom]

Somewhat strong statement. "They may sound different if they measure differently" would be more correct.

That's true, we've had amplifiers that measure horribly but are perceptually transparent from great-measuring amps. Bad measurements only open the door, but never determine what is the perception by a human being.

 

[ferrellms]

Bob Carver, the brilliant engineer behind many audio inventions, particularly amps, has designed and marketed some of the best tube amps and transistor amps available. He feels that sound is purely a matter of the "transfer function" of an amp - which can be from just about perfect to terrible.

Carver claimed that he could modify one of his solid state amps to sound indistinguishable from an amp of Stereophile's choice. So Stereophile accepted the challenge and offered an amp (unidentified since they would not risk embarrassing any of their advertisers) that was known to be idiosyncratic and fussy and expensive, but beloved by high-enders.

So Carver went to work by comparing the electrical output of the amps into Stereophile's test speakers and tweaking the solid state amp to "null" with the Stereophile amp. It was some work, but when done, the amps were indistinguishable from each other to the "golden ears" at Stereophile through the test speakers.

So, different amps, tube or otherwise, can sound different if their transfer functions are different under a particular test input with particular speakers. But those differences will be objectively measurable.

The next question could be "Which sounded better" before the mods were done? Take your pick, but you can bet that Carver's solid-state amp was closer to a straight wire with gain.

 

[Willem]

The two most important reasons for the difference, whether audible or not, are distortion and frequency response due to interaction with the speaker. Properly designed solid state amplifiers have lower distortion and a lower output impedance and therefore interact less with the speaker's impedance. So if you want a straight wire with gain, it is a no brainer. If you want candle light ....

 

[Jimbob54]

Tube amps sound different from solid state amps. Its not about better or worse, its about a difference. For those who thought that they sound same as solid state amps, well, I have to say they are all wrong.

This video from audioholics is a great one and provides the key reasons why they sound different. One of the main reason is distortion. Its measurable.

This is the second such post of yours I have seen. The other was saying tubes and vinyl are preferred to solid state/ digital and asking why (rhetorical?)

I am unsure if you think you are educating, challenging or enquiring but you come across as a mixture of all three.

 

[Zensō]

This is the second such post of yours I have seen. The other was saying tubes and vinyl are preferred to solid state/ digital and asking why (rhetorical?)

I am unsure if you think you are educating, challenging or enquiring but you come across as a mixture of all three.

And there’s the fourth possibility (trolling).

 

[Wes]

I pick door #4

 

[Blumlein 88]

Bob Carver, the brilliant engineer behind many audio inventions, particularly amps, has designed and marketed some of the best tube amps and transistor amps available. He feels that sound is purely a matter of the "transfer function" of an amp - which can be from just about perfect to terrible.

Carver claimed that he could modify one of his solid state amps to sound indistinguishable from an amp of Stereophile's choice. So Stereophile accepted the challenge and offered an amp (unidentified since they would not risk embarrassing any of their advertisers) that was known to be idiosyncratic and fussy and expensive, but beloved by high-enders.

So Carver went to work by comparing the electrical output of the amps into Stereophile's test speakers and tweaking the solid state amp to "null" with the Stereophile amp. It was some work, but when done, the amps were indistinguishable from each other to the "golden ears" at Stereophile through the test speakers.

So, different amps, tube or otherwise, can sound different if their transfer functions are different under a particular test input with particular speakers. But those differences will be objectively measurable.

The next question could be "Which sounded better" before the mods were done? Take your pick, but you can bet that Carver's solid-state amp was closer to a straight wire with gain.

The target amp Carver emulated was a Conrad Johnson Premier amp. Read about it here.

https://www.stereophile.com/content/carver-challenge

As I recall, he increased the output impedance of his amp, and altered it to add a bit of distortion. The final thing that put it over the hump was to decrease the low end response under heavy load as the C-J didn't hold up into lower frequencies. Then it was judged to sound identical. He mostly used nulling between the two amps to figure out what to change. In his case literally connecting the two amps to each side of a speaker and listening. He achieved eventually a -70 db null using actual loudspeaker loads between the amps.

Also, though less well remembered he took the same Carver amp and successfully emulated an expensive Mark Levinson amp for another magazine.

 

[MattHooper]

I'm not an EE so I'm not qualified to render any opinion from a technical standpoint.

Nor have I performed blind testing with my CJ Tube Amps vs solid state (only sighted comparisons, back in the day...though I've blind tested other audio gear in my home).

As a layman I can only sit back, watch the various debates between people who are more qualified, and infer what I can.

My inferences so far: There is nothing magical about tube amplification that, by default, makes any tube amp sound different from a well designed solid state amp. A competent amp designer can design a tube amp to sound indistinguishable from a solid state amp. (And, in Bob Carver's case, the reverse). Given this fact, and given we are often dealing with, in the big picture, quite subtle levels of distortion, it's likely that a decent portion of the "tube amp sounded different from SS amp" reports were due to expectations/biases etc, more than actual sonic differences.

On the other hand: It seems to me that a majority of those knowledgeable about amp building acknowledge that, yeah, tube amps have general liabilities vs solid state that, if you aren't really directing your energy at controlling them, it's easy enough to end up with a tube amp that audibly deviates from a solid state amp. Add to this the fact that, given the romantic notion many audiophiles and tube amp manufacturers have about tube amp sound, they essentially WANT a different sound from a tube amp vs a solid state amp. So given that tube amp manufacturers may be more in the "design by listening" group vs solid state, the fact they are seeking some different sound from solid state, and are using methods of evaluation and design that aren't being strictly guided by measurements, it's very plausible many of these tube amps end up reacting differently to a speaker load than a solid state amp, in an audible way. A fair amount of the Stereophile measurements of different tube amps seems to be evidence of this as well.

So, do my Conrad Johnson Premier 12 amps sound different than a competent transistor amp?

Certainly I very strongly perceive a difference whenever I tried going back to solid state - I heard the CJ as producing a slightly rounder, richer, slightly softened, fatter sound, with a slight upper midrange sort of "glow" or air. I prefer it every time next to an SS amp powering my speakers.

But to be consistent, I have to say: I don't know. That is, not with a scientific level of confidence controlled for bias. So I'd never make an objective claim about it.

Is it plausible I'm hearing sonic differences vs an SS amp? Given what I mentioned above, it seems plausible.

Also, adding to this, Archimago recently did a few posts assessing the results of testing for the audibility of types of harmonic distortion in listening to music:

http://archimago.blogspot.com/2020/06/blind-test-results-part-iii-is-high.html

In the comments I gave a link to measurements of the CJ amps and archimago agreed that it's highly plausible the amps are "flavoring" the sound.

So, I just sit back and try to balance everything I seem to have learned so far. The status of my belief is that, yes it's quite plausible my CJs sound different than the SS amps I've tried, and that I like the difference. But I can't know for sure without bind testing. However, at this point I have little urge to do the blind tests: I've already owned the amps for years, I like the sound of my system, and if my perception of their sound is some mixture of real and imagined (or just imagined), I'm ok with that. I also like tube amps conceptually and aesthetically: I like how my amps look, I like the design concept, I like the fact that when I'm looking at the glowing tubes I'm actually seeing the music signal in that glow. Etc.

 

[RayDunzl]

I like the sound of my system

I like mine, too.

Weird speakers, near-antique amplification, seriously cheap subs and manipulated digits, notwithstanding.

 

[Willem]

Quad's Peter Walker once gave me a private version of the famous blind test comparing his three successive amplifier designs, including the much loved first one, with valves. I thought I could hear differences but he wickedly demonstrated that I had just scored a random result. That Quad valve amp was a well designed one, of course, and measurements have shown that it was indeed a good design even though not measuring as well as his later 303 let alone the 405. As he put it, the only meaningful difference apart from manufacturing cost was the power output.
However, I don't think modern audiophool abominations like those from Primaluna would stand a chance.

 

[Blake Klondike]

+1 for sounds different. people with engineering training and test equipment are only taking issue with the idea that tubes sound *better* or *more accurate*. the fact is that they just sound different, and you either like the sound or you don't.

 

[Blumlein 88]

More than just tubes sound different. They are a colored sound. They lack transparency to the input signal. Their performance envelope is a sub-set of the performance envelope of ss amps. They may sound more pleasing in some sense all the same, but not due to superior performance.

 

[escksu]

I pick door #4

Thats because some of you pple are trolling.

https://audiosciencereview.com/forum/index.php?threads/if-tube-sound-is-a-myth-why-tubes.8656/

This is supposed to be a more technical forum but these are the nonsense replies...

 

[MattHooper]

More than just tubes sound different. They are a colored sound. They lack transparency to the input signal. Their performance envelope is a sub-set of the performance envelope of ss amps. They may sound more pleasing in some sense all the same, but not due to superior performance.

That generally agrees with what I seem to hear.

Whenever I've compared my CJ tube amps to solid state amps I've owned (e.g. Bryston 4BST), my immediate impression is always that, while subtle, the solid state amp sound is tightened up and more accurate and uncolored. Especially in transients - tighter, sharper, and bass as well.
Also that little bit of "glow" is gone on the SS amp which can invoke a slightly "darker" overall sound to my ears. I certainly never get the feeling the tubes are more accurate, always the reverse.

But then when I become fascinated with the accuracy and cleanliness of the solid state amp presentation, I keep it in my system. But after a while
I adjust to it's sound, and now that sound has a sort of predictable sameness of it's own. (To be clear: I'm not saying the solid state amp has a "sound" per se, but rather the system/speakers, no matter what amp, utlimately ends up with a certain sound character). Plus, I find I generally enjoy the sound less than with the tube amp. So, I always found that, given no matter what amp is driving the system I ultimately settle on percieving a certain character to the system, it's a matter of choosing which character pleases me more and makes me want to listen more. Back go the tube amps...and..."aaahhhh..."