Sound Quality Vs. Measurements

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Hi N101N,
No one said you had to defend what you like or dislike in music. Not once. Go be yourself.

But, if you want to know how things really work ... the understanding is partially founded in math. The rest is in cold, hard knowledge. I do love the music that technology can replay.

-Chris
 
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N101N,
I don`t feel a need to prove that I like or dislike the sound quality.
... and I said this,
No one said you had to defend what you like or dislike in music. Not once. Go be yourself.
Are you skipping like a broken record or what?

Then you followed that with this ...
Not the sensible mathematics, that is, the unfettered, unaxiomatized arithmetic counting.
To which I can only say that the math we use is proved and tested.
Is what I say comprehensible?
I have to say no. That might explain some of your responses.

-Chris
 
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Hi N101N,
The technical definitions for sound quality are well defined. You are either in agreement, or wrong. However, you can have an opinion to yourself. Unexpressed, it will never be judged.

I honestly don't understand what you mean at this point in time. In a technical sense, an amplifier (in this case) is either accurate or it isn't (to defined limits). Nothing is perfect, and that is recognized when setting standards. So if you set your standard to within 1% THD and IMD, and the amplifier in question performs better than those limits, then that amplifier is accurate to your stated limits. In fact, you could get ISO accreditation for quality as long as you adhere to your stated standards and procedures.

Under those conditions, and to your standards, we would have to agree with the statement if you said that amplifier was accurate. Of course no one might agree with you against what is generally accepted in the market.

-Chris
 
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Hi N101N,
Okay, you're weird. That's okay. :)

In my day to day work with audio equipment on the bench, and using the RTX 6001, there is on heck of a difference between equipment using measurements. These measurements correlate well with what people hear. I am looking at entire spectrum's, not just a number.

-Chris
 
Hi peufeu,
I think we would agree if we frame the question with boundaries.

Yes :D

Using music as a test signal is a bit like skipping the wind tunnel and testing an aircraft directly by flying it, then trying to figure out what went wrong by examining the debris after the crash. It's cumbersome.

Music is a collection of sine waves, and it does have a maximum rate of change at zero crossings most often, unless it is a rare inflection point - yes?

diana.PNG

I got the idea of the large LF sine + small HF sine by looking at a trace like that. This one is a kick drum + snare drum from Diana Krall. The high frequency content rides on the large signal from the kick drum, and the rate of change depends mostly on the high frequency content, which means it's pretty much the same at zero crossing or anywhere else. On a pure note that looks like a sinewave, then max rate of change is near zero. On more complicated music, I don't see why it would be the case.

More specialized tests always reveal some characteristics of an amplifier, but a frequency response test of an amplifier will also reveal ringing. It has to and does.

Yeah but then you have to do a network analyzer sweep for various output voltages and currents, check if the output transistors' increased transconductance with current compromise stability, check close to clipping, etc, whereas the sine+square test is a lot more convenient...

Most of what someone will hear from an amplifier occurs in the 1 watt range

I've measured voltage & current on my speakers while listening, and yeah. IMO chasing low THD at high power can result in designs like CFP output stage whose crossover looks so destroyed it's like the 'muricans bombed some democracy into it.
 
Thus, sometimes Scott Wurcer has used the word stationary in a context where the genius might insist (to anyone except Scott) that the proper in term that context should be 'non-time invariant.

IFAIK semi-conductor physics is physics.

Physics. A time-invariant system quantity, such as a constant position or temperature.
 
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I would rather ask if the OP question is still valid today, and if yes - in what sense, since nowadays more than 90% of new music "recorded for public to own" makes heavy use of digital processing of dubious quality. It's everywhere, from sound samples to voice processors, from master to transmission. In any genre.

So, too often now, I ask myself what should mean Hi-Fi for new music in 2021?

The OP question gives me a sad smile, since for new music 90% of the true reference does not exist anymore: therefore "sounds good" is to be compared only to yourself? Or only for classical or jazz music? Please clarify.
 
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