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AES Paper Digest: Do Audio Op-amps Sound Different?

Jakob1863

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Well, in no way I want to criticize your tests, but my perception is that on a scientific forum like this we should state as facts only things that have been proven by independent parties in a scientific manner.
At that point we have to agree to disagree, but let me add two additional remarks

-) there is routinely no such thing as "proven by independent parties in a scientific manner" wrt published experimental results. You seem to overestimate what the peer review process is intented and able to do. If you are interested i can cite some literature about what editors of journals expect from their reviewers and i could further provide some studies related to the quality of published studies.Their findings don´t deliver corrobation for the assumption that there exists a process of "proven by independent parties...."

-) ask yourself if you take your own assertion (cited above) seriously. Again it isn´t meant offensive just as a description of an often seen routine, as humans tend to accept information that suits their own beliefs and like to question informations (for any reason available) that doesn´t fit.
See for example your like for the post #249. Does it meet your demand for "proven by independent ........" ? :)

Edit: let me again emphasize that we deal only with probabilities that might (or might not be) attributed to hypothesises - so no proofs are possible - and let me restate that there exists something like the "replication crisis in science" .
 
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Krunok

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See for example your like for the post #249. Does it meet your demand for "proven by independent ........" ? :)
No, as what Arnold was talking about could really be measured by equipment and not by ear.

Edit: let me again emphasize that we deal only with probabilities that might (or might not be) attributed to hypothesises - so no proofs are possible - and let me restate that there exists something like the "replication crisis in science" .
This is really where we disagree, so let's agree to that. :)
 

Krunok

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There are low-level things that can happen to speakers, too, but again by and large AFAIK they've been solved for a long time.
IMHO not all of them have been solved with speakers (and with microphones) otherwise we would be able to perform very simple experiment: record human voice, playback the recording and have listener think it was a living being singing or speaking and not a recording. Until we can do that we cannot really claim we have perfected the microphones and the speakers beyond the level of recognition by listener. I do however believe that today's budget DACs, preamps and amps are good enough to do that job, but microphones and speakers are not.
 

Cosmik

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...only things that have been proven by independent parties in a scientific manner.
Of course there's no such thing as scientific proof. You only get proof in maths.
 

Cosmik

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Frank Dernie

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Yes, I believe that was the case. But in that case single DAC conversion from various DAC devices also cannot be detected, right? :D
That has been my experience for all the non-eccentrically engineered DACs I have compared myself, to such an extent that I don't bother any more.
As far as I am concerned DACs are not a part of a hifi system worth comparing. Buy the one with the functions you want, a styling you like at a price you are OK with. SQ differences are bigger elsewhere.
 

Thomas savage

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A few of you need to mind your attitude , I’m not pleased with the general tone of much of the back and forth here. If it continues in this vein I will address the individuals at fault directly with a public warning but for now let this serve as a general warning to all.

Thank you.

 
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No, as what Arnold was talking about could really be measured by equipment and not by ear.
There are situations where crossover distortion was detected using highly efficient loudspeakers or headphones. Sometimes a pure tone, possibly at a lower frequency like 100 Hz was involved. But detection with music has also been reported. It is truly like a rubbing voice coil, so it if you have heard that which is more likely in modern times, then you already have a pretty good idea of what crossover distortion sounds like.
 

Wombat

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There are situations where crossover distortion was detected using highly efficient loudspeakers or headphones. Sometimes a pure tone, possibly at a lower frequency like 100 Hz was involved. But detection with music has also been reported. It is truly like a rubbing voice coil, so it if you have heard that which is more likely in modern times, then you already have a pretty good idea of what crossover distortion sounds like.
Simple circuits. Simple output vs input measurement. Simple comparison. Analysis not difficult. Forget the hearing tool , here. :rolleyes:
 
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I'm listening music, not 19 and 20kHz tones. At my age I cannot hear over 13 kHz, I seriously doubt anyone over age of 50 can. I would say my listening room falls into "normal" category.

When I compare my tube preamp/amp combo (which has 0.5% of cumulative THD) with my Rotel setup, I can tell them apart with good recordings, but not in a way that tube setup sounds distorted, it sounds less "bright". I,m pretty sure though I won't be able to tell the difference in a true blind test.
I'm 60, and I can still perceive up to 17 KHz (actually just a tad higher, but not 18). We don't have CRT TVs anymore, but I could always hear the HF flyback transformer noise when we did (and not all TVs had it, and it varied with whatever was being painted on the CRT), so maybe 15 years ago.
 

Krunok

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I'm 60, and I can still perceive up to 17 KHz (actually just a tad higher, but not 18). We don't have CRT TVs anymore, but I could always hear the HF flyback transformer noise when we did (and not all TVs had it, and it varied with whatever was being painted on the CRT), so maybe 15 years ago.
I seriously doubt you do. For more info check this article: http://www.roger-russell.com/hearing/hearing.htm

However, in case you really do hear 17 kHz at age of 60 I strongly advise you stay away from kryptonite. :D
 

Soniclife

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Just test my hearing, my response falls sharply over 14Khz, I can hear some stuff but only if I turn the vol up, so not really. The CRT noise used to drive me bonkers, so I used to have that level, but not any more, it's probably the only thing I would notice as different sounding, the world sounds the same to me now as it it did.
 

Krunok

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Just test my hearing, my response falls sharply over 14Khz, I can hear some stuff but only if I turn the vol up, so not really. The CRT noise used to drive me bonkers, so I used to have that level, but not any more, it's probably the only thing I would notice as different sounding, the world sounds the same to me now as it it did.
Nah.. Nothing much happening above that level, at least not in music. There are of course bats searching for moths and stuff like that, but who wants to hear that anyway.. :D
 

Frank Dernie

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Just test my hearing, my response falls sharply over 14Khz, I can hear some stuff but only if I turn the vol up, so not really. The CRT noise used to drive me bonkers, so I used to have that level, but not any more, it's probably the only thing I would notice as different sounding, the world sounds the same to me now as it it did.
Quite a few brass percussion instruments have harmonics up to inaudible frequencies but I can't say I notice any difference either as I get older.I put it down to the fact tat we have a short aural memory so the loss of hearing will be far too slow to be aware of.
 

Soniclife

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Quite a few brass percussion instruments have harmonics up to inaudible frequencies but I can't say I notice any difference either as I get older.
They are probably masked by the lower tones as well, You would need to test with a young person and a low pass filter, be interesting how early you can roll off the top end before a prefect hearing person notices with music. Has this been done?
 

Jakob1863

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I have a slightly weak recollection that D.E.L. Shorter (or was it Finchham?) did this sort of experiments already a long time ago (mid seventies?) and found that listeners could detect low pass filtering although their upper hearing limit was at or below the filter frequency. Cascading of low pass filters adds up.
 

Wombat

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I have a slightly weak recollection that D.E.L. Shorter (or was it Finchham?) did this sort of experiments already a long time ago (mid seventies?) and found that listeners could detect low pass filtering although their upper hearing limit was at or below the filter frequency. Cascading of low pass filters adds up.
Can anyone confirm this?
 

Soniclife

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I have a slightly weak recollection that D.E.L. Shorter (or was it Finchham?) did this sort of experiments already a long time ago (mid seventies?) and found that listeners could detect low pass filtering although their upper hearing limit was at or below the filter frequency. Cascading of low pass filters adds up.
That sounds like the analogue filter that was presumably used was rolling off before the frequency being tested. Doing the test with a steep digital filter was what I was thinking about.
 
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