No strawman. The point is not about Class-B or class-A. The point is about something (fatigue is only an arbitrary selected object) that might be able to perceive only after certain period of time where many "things" can happen during the period.
Kgrlee once mentioned that if you cannot hear in a minute (or so) then you cannot even after hours. But I know it is wrong at least from certain point and is easy to prove:
During the blind test you may be tired (long journey, long waiting) but at home you can listen at your best time, which is early in the morning where our body is fresh, environment noise is low, electrical condition is pure (many people turn off their electronics).
Not to mention certain recording that may challenge one of the amplifier more than the others.
That's what I'm not so sure...
I can hear better than many people, but the question is, can I suggest to people who cannot hear well that they should pick what I would???
I believe that to some extent there is no "taste". You cannot say for example you prefer dissonant. It is a theory.
Audio is just like food. Think about something where you can do a good analogy. Do you prefer Coke to Pepsi (or certain beers)? If so, try to do a blind test. If you fail in the blind test, I don't know what you should feel
First, realize that many people measure amps with resistive load. With real speaker unpredictable result may occur.
Okay, now, any 2 popular amplifiers (preferably DIY) fall into this category?
Thinking that blind tests should be time limited is wrong.
With small differences its very likely that sometimes you can hear them and sometimes not.
You can do double blind tests at home, in your own time, take as long as you want. The only restriction is that no one in the room is allowed to know what device is playing.
Duh...
Let's stick to the topic and not get sidetracked by people whose only exposure to ears-only testing is being caught trying to cheat, OK? Remember the Dunning-Kruger Effect.
Back to the topic. I don't see crossover distortion in the measurements. If you look at Figure 8, the curves suggest that THD+N is noise-limited. A look at the distortion residuals could confirm or refute that, but it was apparently added to S-phile's measurement suite after this review appeared 22 years ago.
I measure the performance of my equipment to make sure it is working properly and not distorting the sound. I enjoy it more knowing that it measures well, because I can just enjoy the music rather than trying to pick holes in the reproduction quality.
I've never tried building loudspeakers, I think there would be no peace of mind then because with speakers there is no right answer. 🙂
So blind tests should be done at listeners' convenience? Like at home with several music track for several days? I wish somebody like you live around here 🙂
I have quoted DF96. He is a gentleman. Truth is more important to him than ego (such as being wrong).
Yes it is. And this is the real issue with the Crown and the general PA high power speakers. I think it is not impedance. I'm not sure myself. Big coil, high moving mass, big EMF, whatever it is, I have found that several PA speakers are difficult to "move" by ordinary amplifier.
You just need to mention a few example that I may own, or I can build and check by myself if I can hear the difference.
Imagine the same amplifier, one channel is built using Holco resistors and the other channel using high tolerance carbon resistor (Allen Bradley). Mention the amplifier, I think I will do it.
You prefer to be BIASED by the measurement number than by the visual of the amplifier, right? (You cannot hear 1% versus 2% but you want 0.001%)
Let's say your "number" is 0.1%. Then I will challenge you to blind test a 0.5% and if you fail then you draw your conclusion.
If you cannot hear 1% versus 2% you should be okay with 2% because
Yes. The feedback factor falls off with frequency, so it gets less effective at correcting distortion. Which in this case is very probably crossover distortion.
You got it! Surely you must agree that a measurement of an amp's performance is more relevant to how it sounds than its visual appearance.
I actually have a tube amp that gives these sorts of distortion figures when the volume is cranked a bit. But I keep it around because, all right, I admit I am biased by the appearance of the cool glowing tubes. 🙂
Admit it, you can hear the difference. Add a resistor at the output of your solid state amplifier, then increase its distortion (e.g by reducing feedback), I believe they will still sound different
Not sure how you draw that conclusion- a class A (or AB running "rich") shows the same sort of rise, since the overall open-loop non-linearity is being corrected less. See, for example Classé Audio Fifteen power amplifier Measurements | Stereophile.com (Figure 4) from the same general era (and thus presumably the same test setup).
Well, I know for sure that the Crown isn't class A, and I'd be very surprised if it was running rich. Every PA amp design I've seen tries to run as "lean" as possible. And large-signal nonlinearity ("beta droop") should be negligible in a 2000W output stage running at 1W. So for me that leaves crossover distortion as the main source of nonlinearity in this scenario.
Tho I certainly understand this, it runs counter to my experiences. Notably the speaker contest at Parts Express. I was one of 3 judges and we quickly went thru dozens of speakers. Yes, some sounded like they looked, but more often than not we judges were quite surprised by how good or bad a speaker sounded judging by its looks - even tho looks were part of the evaluation.
We finally gave up guessing what a speaker would sound like based on its appearance. There just didn't seem to be much, if any, correlation.
That was not my only experience with trumped visual bias, just the most notable one.
Maybe an other bias was at work here.
Goal of double blind testing is to eliminate ALL biases, so only ears are used to judge the sound and not memory or other senses.
I would sooner judge a loudspeaker by its appearance than an amp. Loudspeakers are real, mechanical things and intuition at least partly works with them. No blind tests needed to show that a horn loaded bass bin with 2 18" woofers will give more bass than a Bose bluetooth speaker.
On the other hand, there is the Kef LS50, a speaker so ugly that blind listening is mandatory. 😀
On the other hand, there is the Kef LS50, a speaker so ugly that blind listening is mandatory. 😀
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unconscious bias isn't claimed to dominate any/all input from the ears - random loudspeakers can vary by many dB, octaves in on axis response even before considering directivity
but "naïve subjectivists" claim to make subtle, literally "can't be conventionally measured" distinctions in systems where the variable (say, good amplifiers) measure, match orders better than the loudspeakers they are listened to through
the ability "listen through" other not under discussion system elements flaws is also a prime "naïve subjectivists" claim
it seems reasonable the smaller the objective sound wave difference, the more likely extraneous influences become more important
and the ability to seemingly always "listen through" while when confirming audiophile lore and then accusing those insisting on controls of only using unresolving systems, flawed components that destroy the validity of their listening tests is lame
admitting it took a while so the early evaluations were more biased?
why not a curtain, any reasonable attempt at blinding the evaluation of the speaker's sound before/independent of visual inspection rating
but "naïve subjectivists" claim to make subtle, literally "can't be conventionally measured" distinctions in systems where the variable (say, good amplifiers) measure, match orders better than the loudspeakers they are listened to through
the ability "listen through" other not under discussion system elements flaws is also a prime "naïve subjectivists" claim
it seems reasonable the smaller the objective sound wave difference, the more likely extraneous influences become more important
and the ability to seemingly always "listen through" while when confirming audiophile lore and then accusing those insisting on controls of only using unresolving systems, flawed components that destroy the validity of their listening tests is lame
admitting it took a while so the early evaluations were more biased?
why not a curtain, any reasonable attempt at blinding the evaluation of the speaker's sound before/independent of visual inspection rating
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Without either a frequency spectrum at low power or a distortion residual in the time domain, we can only guess. If some kind soul donates one of these to me for testing, I'll gladly post the results.
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