Stereophile Amplification Product of the Year

[Galliardist]

Unfortunately, I have no way of knowing whether some of the opinion leaders have any listening experience with 300B SET amplifiers in a appropriate setup. I take it with a grain of salt.

I'll plead guilty to not having a great deal of listening experience. It didn't take me long to decide it wasn't my thing.

It does lead to the inevitable question, though: if my sighted preference happens to be closer to the expectations of this forum, is it more valid?

Even though I'll always argue that a new starter should begin with auditioning neutral electronics and correctly designed speakers by the light of this forum and the best science we have for controlled listening, because that is the statistically most likely to work, that's a different thing from my sighted preference being close-ish to that, right?

 

[Hauxon]

If the sound isn't making you happy? Um, what was your point again?

The obvious limitation is power and it is pretty easy to reach.

 

[fpitas]

So a SET tube amp will offer "pure" amplification

That's a puzzling use of that word.

 

[Hauxon]

I'll plead guilty to not having a great deal of listening experience. It didn't take me long to decide it wasn't my thing.

It does lead to the inevitable question, though: if my sighted preference happens to be closer to the expectations of this forum, is it more valid?

Even though I'll always argue that a new starter should begin with auditioning neutral electronics and correctly designed speakers by the light of this forum and the best science we have for controlled listening, because that is the statistically most likely to work, that's a different thing from my sighted preference being close-ish to that, right?

When you say neutral electronics and correctly designed speakers it is still objective. You might assume a tube colorizes the signal and it truly does when reaching it's limits but a non overdriven tube might still be called the purest form amplification that does not need to remedy the 0.7V operating threshold of a silicon transistor, it simply amplifies what you serve it. Like I said it's objective and depends on personal perspective. ..and for speakers what is correctly designed? Are horn acoustics incorrect? How about the cabinet, or open baffle? ...crossover components and design?? What's correct for who and what?

 

[fpitas]

When you say neutral electronics and correctly designed speakers it is still objective. You might assume a tube colorizes the signal and it truly does when reaching it's limits but a non overdriven tube might still be called the purest form amplification that does not need to remedy the 0.7V operating threshold of a silicon transistor, it simply amplifies what you serve it. Like I said it's objective and depends on personal perspective. ..and for speakers what is correctly designed? Are horn acoustics incorrect? How about the cabinet, or open baffle? ...crossover components and design?? What's correct for who and what?

I'm sorry, your grasp of devices and circuit design is not very good. Tubes distort, like all devices.

 

[Hauxon]

If the sound isn't making you happy... Um, what was your point again?

Oh, before I forget, welcome to ASR.

Thank you. I've been a lurker for years.

 

[Hauxon]

I'm sorry, your grasp of devices and circuit design is not very good. Tubes distort, like all devices.

Yes true. Don't know what you mean however with grasp of devices and design. I do not present myself as a all knowing person about amp design. I have however taken a year long hands on course in amplifier design so I know at least the principles of how amplifiers work and how to make them, both tube and transistor based. As I see it there is no finite correct design. All designs have limitations and the amp design has to decide to what boundaries apply.

I stand by what I said in my first comment. Not all types of distortion are equal. Second-order harmonics can be somewhat tolerated while third-order harmonics are perceived (heard) much earlier. For a THD measurement to be meaningful it must be in relation to the human ear and perception.

 

[fpitas]

In any event your broad statement about tube distortion was incorrect. SETs in particular usually show a constantly rising distortion with output level.

 

[Galliardist]

Yes true. Don't know what you mean however with grasp of devices and design. I do not present myself as a all knowing person about amp design. I have however taken a year long hands on course in amplifier design so I know at least the principles of how amplifiers work and how to make them, both tube and transistor based. As I see it there is no finite correct design. All designs have limitations and the amp design has to decide to what boundaries apply.

I stand by what I said in my first comment. Not all types of distortion are equal. Second-order harmonics can be somewhat tolerated while third-order harmonics are perceived (heard) much earlier. For a THD measurement to be meaningful it must be in relation to the human ear and perception.

It's not so difficult, though, to find amplification and a digital source that do not have audible amounts of any harmonic distortion in normal use. So why have "tolerated" levels of second order harmonics? Is that better than inaudible? Can you demonstrate that all distortion is in fact audible, or something similar, to disprove that as an assertion?

To reply to your previous question to my post: for speakers, look at the Harman research in the first instance for what is preferred, and bear in mind the influence of the room.

Obviously, devices have to be used within their design parameters to work correctly.

 

[rdenney]

Second-order harmonic distortion might not be as objectionable as other distortions, but it’s still distortion. I wouldn’t want somebody’s playback system messing with the harmonic content Pop Johnson designed into the Chicago Symphony’s York tuba, for example. That second-order distortion is like a Hammond organist pulling the 4’ slider when playing a low C, and I wouldn’t want the playback system telling Keith Emerson or Jon Lord he didn’t pull the slider enough, for another example.

Let’s leave the art to the artists and keep the playback linear and undistorted, please.

Rick “whose listening experience is mostly in person” Denney

 

[fpitas]

Second-order harmonic distortion might not be as objectionable as other distortions, but it’s still distortion. I wouldn’t want somebody’s playback system messing with the harmonic content Pop Johnson designed into the Chicago Symphony’s York tuba, for example. That second-order distortion is like a Hammond organist pulling the 4’ slider when playing a low C, and I wouldn’t want the playback system telling Keith Emerson or Jon Lord he didn’t pull the slider enough, for another example.

Let’s leave the art to the artists and keep the playback linear and undistorted, please.

Rick “whose listening experience is mostly in person” Denney

The dark side of the "harmless" 2nd harmonic distortion is IMD mixing products. Not a problem with very simple music, but it gets out of hand rapidly with complex material.

 

[DonR]

"musical" ... that word again. Audio reproduction equipment is not and should never be seen as a musical instrument.

 

[Hauxon]

It's not so difficult, though, to find amplification and a digital source that do not have audible amounts of any harmonic distortion in normal use. So why have "tolerated" levels of second order harmonics? Is that better than inaudible? Can you demonstrate that all distortion is in fact audible, or something similar, to disprove that as an assertion?

Here the word audible is the key. When does harmonic distortion become audible and at what frequencies? Distortion has no meaning to the listener until it's heard. That's why the Audio Note amp may still sound good even if distortion is high compared to a transistor amp. It doesn't make the amp any better or worse, it just doesn't matter since it's second-order harmonics are not audible. Not better, just isn't relevant.

As I see it distortion measurements have in general little meaning unless the amp is underpowered and then it just the wrong amp for the job. I still haven't built a class D amp so don't know much about 'em. My next project actually is a power amp based in the IcePower 1200AS2 and I might add a NuTube buffer to it. Won't get any awards but might satisfy me.

 

[Hauxon]

"musical" ... that word again. Audio reproduction equipment is not and should never be seen as a musical instrument.

Musical just means not hurting your ears as much.

 

[fpitas]

the Audio Note amp may still sounds good even if distortion is high compared to a transistor amp

Which seems to obviate the purpose of paying extra and putting up with its other foibles.

 

[Ken1951]

Let’s leave the art to the artists and keep the playback linear and undistorted, please.

Yes

"musical" ... that word again. Audio reproduction equipment is not and should never be seen as a musical instrument.

And, yes!

 

[fpitas]

"musical" ... that word again. Audio reproduction equipment is not and should never be seen as a musical instrument.

Exactly. This is "reproduction", not production.

 

[DonR]

Musical just means not hurting your ears as much.

I see. Iggy city.

 

[rdenney]

Here the word audible is the key. When does harmonic distortion become audible and at what frequencies? Distortion has no meaning to the listener until it's heard. That's why the Audio Note amp may still sound good even if distortion is high compared to a transistor amp. It doesn't make the amp any better or worse, it just doesn't matter since it's second-order harmonics are not audible. Not better, just isn't relevant.

As I see it distortion measurements have in general little meaning unless the amp is underpowered and then it just the wrong amp for the job. I still haven't built a class D amp so don't know much about 'em. My next project actually is a power amp based in the IcePower 1200AS2 and I might add a NuTube buffer to it. Won't get any awards but might satisfy me.

It seems to me that there are two features of this amp that are likely to be audible. 1% harmonic distortion is likely to be audible to a careful listener in an A/B test, but this amp exceeded that at power above--what was it?--900 mW. And that leads me to the second issue. In any realistic listening environment with normal speakers place more than a foot or two from the listener, this amp will clip, sending distortion much higher. That will certainly be audible. So, yes, this amp is certainly underpowered, but the question I have is: Is it so underpowered that it's "just the wrong amp" for any job? I can't think of how any amp can "let the music shine through" without playing loudly enough to get the quiet bits out of ambient room noise, unless a person only listens to brickwalled pop music. But that music was certainly NOT intended to be listened to quietly.

Frankly, I've seen better distortion and power specs on battery-powered transistor radios.

Rick "whose idea of hi-fi has always required abundant power to prevent clipping at realistic levels" Denney

 

[fpitas]

Musical just means not hurting your ears as much.

Comments like that just confirm my impression that some people are covering up slight imperfections in their playback chain by using distorting amps, and even vinyl with its groove noise.