He has said earlier that he has the [a href='index.php?act=findpost&pid=113']'luxury'[/a] of not having to bother too much about thresholds, he wants to make stuff with a safety factor. This is entirely rational, as a luxury: it would seem that if one used that sort of equipment, one could kick out the jams and play music at unusual, or even unwise, levels and still be sure of not hearing artifacts.

The average consumer has no idea how bad their CD player or sound card really is.  There often are no published specifications.

The average consumer has no idea how bad their CD player or sound card really is.

Your statement makes it seem like there is a lot of junk out there, but I won't believe such a statement unless some measurements and blind tests results are posted.

Could I, with genuine respect, make a small observation here. People are wanting John_Siau to engage in a debate on audibility thresholds. He has said earlier that he has the [a href='index.php?act=findpost&pid=113']'luxury'[/a] of not having to bother too much about thresholds, he wants to make stuff with a safety factor. This is entirely rational, as a luxury: it would seem that if one used that sort of equipment, one could kick out the jams and play music at unusual, or even unwise, levels and still be sure of not hearing artifacts.

I say that because there's a slight tendency to attribute to him scepticism about ABX tests. That is not at all the case, it's just that, for him,
audibility in a blind test is not the design target, but rather the certainty of inaudibility even in extreme cases.

That would seem to suggest a concrete counterexample to Meyer/Moran, except for the fact that 100dB A-weighted slow seems extremely loud to me. You could only play 2 CDs at that loudness a day before exceeding OSHA occupational noise limits.

If used with "uncompressed" music, suggesting a crest factor of 20db, you're looking at peak SPLs in the 120-130dB range. I'm not really sure that is a normal playback level to begin with.

There is an entire ecosystem of false information, over-priced products, magazines that pontificate on said information and products, and then tons of forums where the audiophiles all sit around and agree with each other. Once you buy into it, you get constant reinforcement. The more strongly you believe, the more of it you will take in and believe.

But he's also the one making claims edging towards *routine* audible difference in CDPs under normal listening conditions (Although whether the conditions cited are 'normal' is also under dispute; I've seen no address yet to this point of Axon's:

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That would seem to suggest a concrete counterexample to Meyer/Moran, except for the fact that 100dB A-weighted slow seems extremely loud to me. You could only play 2 CDs at that loudness a day before exceeding OSHA occupational noise limits.

If used with "uncompressed" music, suggesting a crest factor of 20db, you're looking at peak SPLs in the 120-130dB range. I'm not really sure that is a normal playback level to begin with.

Free passes for audio claims have done enough damage to the hobby already. As tiptoe eloquently noted on the 'do we need audiophiles' thread:

There is an entire ecosystem of false information, over-priced products, magazines that pontificate on said information and products, and then tons of forums where the audiophiles all sit around and agree with each other. Once you buy into it, you get constant reinforcement. The more strongly you believe, the more of it you will take in and believe.

Remember, if you are going to make claims about audible differences in sound quality, they must be accompanied with double-blind test results.

What do you want? Ending the discussion, because luxury must stay exempt from reason? That would be both boring and inconsistent.

So ABX tests regarding high end DACs should not prohibit unusual levels, only those where it gets pathological (like >106 db for more than 30 minutes).

But he's also the one making claims edging towards *routine* audible difference in CDPs under normal listening conditions

That, I think, is your suspicion talking. I have not so read him.

Quote from: krabapple on 2009-08-07 19:29:11

But he's also the one making claims edging towards *routine* audible difference in CDPs under normal listening conditions

It is common to acknowledge, here, that a difference is audible between 16-bit and 24-bit when played at unusual (but not fatal) levels. As I said, there may well be people who are prepared to risk a bit of hearing loss to, just occasionally, really crank it up. It might be unwise, but as long as it's their decision, why not include this unusual case in the design targets.

Quote from: krabapple on 2009-08-07 19:29:11

But he's also the one making claims edging towards *routine* audible difference in CDPs under normal listening conditions

That, I think, is your suspicion talking. I have not so read him. It is common to acknowledge, here, that a difference is audible between 16-bit and 24-bit when played at unusual (but not fatal) levels. As I said, there may well be people who are prepared to risk a bit of hearing loss to, just occasionally, really crank it up. It might be unwise, but as long as it's their decision, why not include this unusual case in the design targets.

I am NOT questioning the value of all the careful work that has been done on the limits of hearing. (Also, I myself have crappy hearing and don't ever intend to spend real money on audio equipment--I'm more interested in music). But there is a tendency to be really fundamentalist about it. I can not see that it is any kind of crime against reason to design to better than audibility threshold, and to say so. That is what I mean by luxury. Except, of course, that in professional use, it might not be luxury. Not even the fundamentalists question using 24/96 for recording and processing.

Also, a manufacturer of high quality equipment is NOT responsible for the garbage put out by scam artists. Another point that fundamentalists find hard to accept.

Btw, your use of the label 'fundamentalist' is hardly conducive to the amity you're advocating.

Quote from: krabapple on 2009-08-08 17:13:42

Btw, your use of the label 'fundamentalist' is hardly conducive to the amity you're advocating.

Oh, I'd quite got over amity. I was pissed off at the suspicion and hostility that was starting to show towards a rational contributor.

"Fundamentalist" was mostly trolling, but not entirely, because there is a mindset around that says because 44/16 is enough, it's somehow a betrayal to use more (more headroom is a kind of concession to human weakness, or something).

There's even sometimes a suspicion of using measurements. Surely the great achievement of the last 50 years or so is to discover what actually makes a difference to perception, and what instrumental measurements are relevant, and what numbers. Of course, DBT is vital to validate and calibrate this, but surely engineers find it much easier to design and develop to criteria that can be measured instrumentally? Check, if necessary, by DBT at the end.

But what some people might want to do (e.g. John_Siau) is to say something like "<defect> may be audible at, say, -70 db, so I'll design to -100, because if I designed to -75, I'd have to run a DBT."

And what is fundamentalist is to take a statement like that and challenge it on grounds of suspicion of heresy--"How do you know it might be audible at -75? How dare you act on that untested assumption?".

The problem with fundamentalism is not what is believed, but how it is believed. And I've seen before that someone with a rational and perhaps verifiable point gets attacked because it looks like it challenges the established view. I'm thinking of the thread on the possibility that a cartridge has a compensating error in stereo reproduction which might mean that you can get a better stereo image with vinyl. That idea got flamed because people thought it was just another vinyl-is-better rave. That failure to actually listen, and the manichaean division of the world into the enlightened and the phools, seems reasonable to call fundamentalist.

You are distorting reality. Current reality is that just about the cheapest DAC that's worth the trouble to stick on a circuit board has maybe 90 dB or better dynamic range. Nobody is using 70 dB DACs as their baseline any more, except maybe people building $20 or cheaper portable CD players.

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And what is fundamentalist is to take a statement like that and challenge it on grounds of suspicion of heresy--"How do you know it might be audible at -75? How dare you act on that untested assumption?".

It's 2009, and your argument is off by over 20 dB. That makes it a straw man argument whether you know it or not.

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... there is a mindset around that says because 44/16 is enough, it's somehow a betrayal to use more (more headroom is a kind of concession to human weakness, or something).

It's not a betrayal, its just a waste.

In this day and age, building a DAC with 100 dB dynamic range is almost a slam dunk. But, building a true 24 bit DAC is mission impossible. Why put a ton of effort into doing something that's going to be difficult and costly?

• Connect the MBP's line-out into its line-in with a loopback cable (1. run) / connect the MBP via Toslink to the DAC1 and its outputs to the MBP's line-in (2. run).
• Set Mac OS X's audio parameters to output 44.1 kHz/24 bit, input 96 kHz/24 bit.
• Playback fullscale 1 kHz sine wave to adjust input gain to just below clipping.
• Record while playing back tec_sqam_40a test sample.
• Normalize recorded sample to -1 db.

• Normalize tec_sqam_40a to -1db and convert its sample rate to 96 kHz (Audition 3, highest quality, without pre/post filtering).
• Synchronize recorded samples' time/offset to tec_sqam_40a's with Synchrotron.
• Invert/restore phase of DAC1 recording.*
• Set Mac OS X's output parameters to 96 kHz/24 bit.
• Plug headphones into DAC1.
• ABX with Foobar in VMware Fusion virtual machine.

foo_abx 1.3.4 report
foobar2000 v0.9.6.8
2009/08/12 00:57:02

File A: Z:\rpp3po\Downloads\rec_dac1_24_inverted.wav
File B: Z:\rpp3po\Downloads\rec_mbp_24.wav

00:57:02 : Test started.
00:58:02 : 01/01  50.0%
00:58:08 : 02/02  25.0%
00:58:21 : 03/03  12.5%
00:58:32 : 04/04  6.3%
00:58:41 : 05/05  3.1%
00:58:50 : 06/06  1.6%
00:58:59 : 07/07  0.8%
00:59:14 : 08/08  0.4%
00:59:26 : 09/09  0.2%
00:59:42 : 10/10  0.1%
00:59:43 : Test finished.

 ---------- 
Total: 10/10 (0.1%)

• Set Mac OS X's audio parameters to output 44.1 kHz/24 bit, input 96 kHz/24 bit.