Do you prefer SS or tube? Why?

Anatta said:
Afraid to ask but, what do you mean? Are you one of the zombies out there chanting the Feedback is evil mantra btw?



No, the story that emerges is that no toob amp, irrespective of cost, can be as clean as a good SS amp even at mW power level (as if that has any relevance anyway in the real world).
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It still has very low distortion , how much distortion is too much ..?
 
a.wayne said:
Tell me something i don’t know .. :rolleyes:
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Well, if you do know, what was this upward distortion curve graph supposed to show?

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a.wayne said:
John usually post graphs which is distortion only vs frequency less the noise
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Yes he does, so? How is that relevant to distortion vs power?

a.wayne said:
BTW, whats odd about that graph you posted ...?

Clip much ... :)
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You mean the hard clipping? How about not clipping the amp?
 
Anatta said:
Well, if you do know, what was this upward distortion curve graph supposed to show?

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Yes he does, so? How is that relevant to distortion vs power?



You mean the hard clipping? How about not clipping the amp?
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How low the distortion and noise is at mW levels, also the gradual rise in distortion means the transition to higher thd and clipping is not as noticeable and actually is much more natural to our hearing as it mimics sound in real life ..

Regards
 
a.wayne said:
How low the distortion and noise is at mW levels, also the gradual rise in distortion means the transition to higher thd and clipping is not as noticeable and actually is much more natural to our hearing as it mimics sound in real life ..
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But it ain't lower than SS so basically you had no point the whole time.

How the amps clip is irrelevant to how linear they are within their power limit. And I'd prefer the clipping to be as noticeable as possible so I can avoid it.
 
Anatta said:
Yes, tube amps sound smoother due to more distortion, not less. Why the 50Hz graphs should go to 10kHz when the harmonics don't even reach 1kHz? How is it of any relevance the specific amp models? But if it helps you:

for the 50Hz: 1st Benchmark AHB2, 2nd Boulder 2150, 3rd Audionet Max
for the 1kHz: 1st Benchmark AHB2, 2nd Audionet Max, 3rd Musical Fidelity AMS100
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No links there. The reason is our ears are tuned to birdsong frequencies (Fletcher-Munson). It matters what distortion harmonics are turning up in that range; that's a range that if enhanced, will be described as 'bright'.
Now you're blaming the measurement and the power chord?
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Was I not clear about that?

Yes, if and when the distortion raises above the noise. If not, you'll just have a straight downward curve right until clipping. Any amplifier, tube or SS, SE or PP, has less distortion at low power than at high power.
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You do realize a problem here, right? Why would noise increase at lower powers? Noise is in any amp I'm aware of, a constant.
 
Anatta said:
Are you seriously asking this question? For real?
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Sounds like an impasse to me.

Put another way, noise is a constant and does not increase at lower power levels, but distortion commonly does. Spend some time with an amplifier, a sine oscillator and a few amplifiers and you will see what I mean.
 
atmasphere said:
Sounds like an impasse to me.

Put another way, noise is a constant and does not increase at lower power levels, but distortion commonly does. Spend some time with an amplifier, a sine oscillator and a few amplifiers and you will see what I mean.
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Lol, noise is constant, but the output power is not; when the output power lowers, the noise becomes a bigger part of the amplifier's output signal percentage wise, hence the higher THD shown at low power for low distortion amplifiers in the THD+N measurement. What you see as increased distortion at low power in the THD+N measurement is just the noise becoming a bigger part of the output signal, not distortion.

You do an FFT measurement of any correctly biased amplifier (to avoid crossover distortion), tube or SS, at 1W and at higher power, within the amplifier limits, and the 1W measurement will always be much cleaner. And SS amps are cleaner than tube amps at low power, tough luck.
 
I guess actually looking at amplifier sine wave performance on the bench doesn't count, huh? Weird how you can actually see some amps distort when at higher power levels they don't. I used to be a service technician- that's how I supported myself when putting myself through college to get my degree. I've seen a lot of amps that were biased to the specification and also had distortion issues at low power. Easy to see on the 'scope. Just for fun I would mess with them to see what they would do if I increased the bias and in many cases got rid of a lot of distortion artifact. But they were then running bias levels higher than spec and tended to idle warm. My suspicion is that they were biased in such a way as to deal with the fact that they had inexpensive heatsinks. So 'all' being an inclusive term IME makes your comment false. 'Some' would make it true, as in 'some amps when properly biased will have decreasing distortion as power levels are reduced to zero.'

I have a little class D amp on my bench that is a small circuit board. Its distortion is dramatically higher at lower powers and its not noise- its distortion. Apparently the designer decided to not worry about offset margins at the comparator and you can hear it easily enough. But when you turn it up it sounds alright. Its class D- there are no bias adjustments of course....

FWIW, SETs have the property of unmeasurable distortion at low power levels- which is why if you really want to heat what an SET does its pretty well essential to have a high efficiency loudspeaker.
 
This would seem like a slam dunk in your favour, but we're not seeing these plots actually address my comment that you quoted. I don't see 1/2 watt, 1/4 watt and so on. When you're playing an SET, IMO/IME its really a good idea to avoid going more than about 20% of full power if you really want to get what the SET is all about. And this is just me personally, I have a hard time taking SETs seriously that are much more than about 7 watts as they often have bandwidth problems. So I'm talking about some pretty low powers here, since you need a fairly high efficiency loudspeaker to hear that 'first watt' properly. I know a lot of SET owners won't agree with me on this but that has been my position for a long time. I don't see these plots addressing this.
 
These plots address your BS that tubes have lower distortion at low power than SS and that SS has higher distortion at low power than at high power. You gotta keep the BS audiophile myths alive, don't you?

So the Lamm ML3 is no good; at 1W is no good (too much power). Ok.

Sophia Electric 91-01 300B @ 1V into 8 Ohm (125mW)
https://www.stereophile.com/content...1-300b-monoblock-power-amplifier-measurements
1213Sophfig12.jpg


Thoress 300B @ 500mW
https://www.stereophile.com/content/thöress-300b-monoblock-power-amplifier-measurements

415TH300fig09.jpg


Yamamoto A-08 @ 100mW
https://www.stereophile.com/content/yamamoto-08-power-amplifier-measurements

306YAMFIG09.jpg
 
Actually no. I just want to get to the bottom of it. I don't want to promote BS and FWIW you've been convincing me that I have to look a lot deeper into this subject. Thanks for taking the time to dig this up. I still find it troubling that the distortion components in the 4-7KHz range aren't displayed when the test tone is 50Hz. Its that region where the biggest issues that people tend to have with solid state are brought up- brightness and harshness. I've always thought is was higher orders like the 5th and above, but now I'm thinking that the actual distortion components might be much higher than that in some cases. IOW I still feel that distortion is at the root of the tubes/transistors debate.

Is it your surmise then that distortion is why tubes sound smoother?? Or is it something else?

It might interest you to know that we've been working on our own class D amplifier for the last two years; for which we have filed for a patent. The patent relates to the elimination of the need for dead time circuitry and thus reduces the distortion of the amplifier and IME relates directly to this topic.
 
Atmosphere, I’m a senior with chronic tinnitus. I have a lovely nc500 based amp with great detail and soundstage. But, and I don’t think I’m imagining this, it seems to aggravate the ringing in my ears. There’s nothing audible I can point to, and I love the sound, but it does seem to aggravate my tinnitus.

Do you have an opinion on whether class D does this, and if so, why?

thanks
 
Al M. said:
An article that I found enlightening:

Katz's Corner Episode 25: Adventures in Distortion
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Thanks- that backs up a number of the ideas I had (masking), and the idea that quite often loop feedback is poorly applied.


Samoyed said:
Atmosphere, I’m a senior with chronic tinnitus. I have a lovely nc500 based amp with great detail and soundstage. But, and I don’t think I’m imagining this, it seems to aggravate the ringing in my ears. There’s nothing audible I can point to, and I love the sound, but it does seem to aggravate my tinnitus.

Do you have an opinion on whether class D does this, and if so, why?

thanks
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I don't think class D in general would do that, but it could well be that a specific class D could... have you tried other amplifiers to see?
 
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