[RRod]

 

 
Thanks for the elaboration, and basically confirms that I've given hi-res its own fair chance as far as my own personal testing.

 

[RRod]

Where things get a little tricky is that not all information can be expressed as a frequency. For example, a square wave is a collection of several harmonics, in particular proportions, and in a particular phase relationship to each other. If the frequency response of a device or recording isn't correct, then square waves played through it will both look unusual and sound wrong. However, if the frequency response is correct, but the phase response is wrong, you can end up with a signal that contains all the right amounts of energy at each frequency, but has a waveform that looks nothing like the original. Since our hearing seems to work mostly by analyzing energy like a spectrum analyzer, this difference is mostly inaudible. However, some research suggests that we are in fact somewhat sensitive to some aspects of the shape of the waveform itself - like the precise arrival time of the leading edge of it. One theory is that, even if we include all the audible frequencies up to 20 kHz so that we don't hear anything missing, because the missing harmonics above 20 kHz contribute to the overall shape of the wave, some other aspect of our hearing (perhaps the mechanism that figures out spatial location from phase relationships) may detect that the wave shapes are now incorrect, which may result in a perceived shift in the location of that instrument in the sound stage. In other words, the basic claim is that, even though we don't "hear" sound above 20 kHz, some of that information above 20 kHz does in fact contribute to other things we perceive about the sound - like its location - or even some other as yet not fully defined detail. And so we somehow sense when that information is altered or discarded. There have been some tests that at least suggest that this may happen - but they are far from conclusive. There is also lots of anecdotal evidence that a lot of people claim to hear a subtle difference.

 
So what would it take to convince someone on such a point. My feeling is that I've taken an ideal 1k square wave at a silly high rate (256*48000), decimated it down to a 96ksps file A, sinc filtered everything above 20kHz to make file B, ABXed A and B and haven't hear a whit of difference, and that's getting pretty much as many leading edges into my ears as I can. Any phase errors introduced by either the resampling or my DAC+amp would be in there too.
 
The frustrating thing is that such a test is considered, on most of this site at least, nothing next to some guy "sensing" a difference in his transients in an sighted evaluation of two different masters of a recording made on tape.

 

[JWolf]

A 1k square sine wave is worthless as a test when talking about complex music.

 

[RRod]

  A 1k square sine wave is worthless as a test when talking about complex music.

 
Point proven.

 

[interpolate]

Don't get me wrong what high res recordings or sacd quality masters i own are subliminally different rather than distinctly audibly different.

My own 24-bit files are less susceptible to aliasing when mixed with other waveforms.....whatever that means.

 

[KeithEmo]

I agree with you entirely - and I'm afraid I've been playing Devil's advocate here because I get very OCD when people make generalizations. In science, it is very difficult to prove absolute generalizations, especially when a subject as variable as human beings is involved. And, while I'm inclined to take the side that the majority of weird things that audiophiles believe really are the result of placebo effect or some other sort of expectation bias, I've also seen a few that weren't - which makes me unwilling to make blanket statements without lots of corroborating evidence. (And I can name you several instances of blanket statements about audio that have in fact turned out to be wrong, or to have easily demonstrable exceptions.)
 
So, to answer your question.... Because the differences themselves are easily measured, and all we're talking about is the limits of human perception, which I don't believe have been fully explored, it would take a lot of evidence to convince me of the generalization - and I don't honestly believe anyone is going to expend the effort and expense necessary to explore the subject that thoroughly.
 
Therefore, I would much rather simply rephrase it as a practical question rather than an absolute generalization.....
 
- Have I ever heard a difference between a high-res file and the equivalent standard-res file where I could say with certainty that the difference was audible BECAUSE the file was a high-res file and wasn't due to mastering differences or conversion artifacts? No.
 
- Am I aware of any test that has shown that a statistically significant number of people could hear such differences? No.
 
- Would I suggest that someone should buy the high-res version of a file even if they can't hear a difference? Probably not.
(But I wouldn't discourage someone from buying a high-res version of an album that sounded better - even if there was a distinct possibility that the real difference was due to different mastering or something else.)
   

   
So what would it take to convince someone on such a point. My feeling is that I've taken an ideal 1k square wave at a silly high rate (256*48000), decimated it down to a 96ksps file A, sinc filtered everything above 20kHz to make file B, ABXed A and B and haven't hear a whit of difference, and that's getting pretty much as many leading edges into my ears as I can. Any phase errors introduced by either the resampling or my DAC+amp would be in there too.
 
The frustrating thing is that such a test is considered, on most of this site at least, nothing next to some guy "sensing" a difference in his transients in an sighted evaluation of two different masters of a recording made on tape.

 

[JWolf]

The more bits there are the more accurate the sampling.  If you convert an analogue signal to digital and back again you introduce quantisation errors, in both processes, leading to distortion.  With 24 bits the size of the errors are about one thousandth of those occurring when 16 bits are used.  This is what is relevant, not the dynamic range (which, as mentioned, is adequately covered by 16 bits).
 
 

 

[RRod]

  The more bits there are the more accurate the sampling.  If you convert an analogue signal to digital and back again you introduce quantisation errors, in both processes, leading to distortion.  With 24 bits the size of the errors are about one thousandth of those occurring when 16 bits are used.  This is what is relevant, not the dynamic range (which, as mentioned, is adequately covered by 16 bits).
 
 
 

 
You have assumed that, because the quantization errors are smaller, they are less audible, which is of course the exact thing that you need to prove.

 

[Arunabha Lahiri]

Yes I agree. But the quantization error is hardly noticeable in 16 bit audio in normal audio playback volume. And nobody listen to music that loud, it will cause permanent deafness. So I guess that's another argument against 24bit audio.

 

[Arunabha Lahiri]

You have assumed that, because the quantization errors are smaller, they are less audible, which is of course the exact thing that you need to prove.

Actually he is right as quantization errors are smaller, they are less audible. Higher bit rates do result less quantization noise. And higher bit rate do mean higher dynamic range. There is more difference in the loudest part and the softest part. A 16 bit recording has a dynamic range of near 120 dB. A 24 bit recording has max dynamic range 144dB.a human ear has dynamic range of 140 dB. So 16 dB recording is more than enough to completely cover up the quantization noise. In fact to hear the quantization noise there should be a music volume of 96dB higher than the quantization noise. And that's absurd. So 16 bit is more than enough. 24 bit is kinda unnecessary. Though human mind works in a strange way. And belief is the greatest religion in the universe.

 

[RRod]

Actually he is right as quantization errors are smaller, they are less audible. Higher bit rates do result less quantization noise. And higher bit rate do mean higher dynamic range. There is more difference in the loudest part and the softest part. A 16 bit recording has a dynamic range of near 120 dB. A 24 bit recording has max dynamic range 144dB.a human ear has dynamic range of 140 dB. So 16 dB recording is more than enough to completely cover up the quantization noise. In fact to hear the quantization noise there should be a music volume of 96dB higher than the quantization noise. And that's absurd. So 16 bit is more than enough. 24 bit is kinda unnecessary. Though human mind works in a strange way. And belief is the greatest religion in the universe.

 
If the quantization on 16 bits is already inaudible under normal listening conditions, then it isn't any less audible in 24-bits. So we're in agreement but for semantics.

 

[Arunabha Lahiri]

If the quantization on 16 bits is already inaudible under normal listening conditions, then it isn't any less audible in 24-bits. So we're in agreement.

Yes we are.. Technically we both are stating the obvious.

 

[coli]

  The more bits there are the more accurate the sampling.  If you convert an analogue signal to digital and back again you introduce quantisation errors, in both processes, leading to distortion.  With 24 bits the size of the errors are about one thousandth of those occurring when 16 bits are used.  This is what is relevant, not the dynamic range (which, as mentioned, is adequately covered by 16 bits).
 
 
 

Actually, I have never heard any difference between 24/16bits. Sample rates yes, but not bit rates. And I have a very accurate setup nowadays.
 
Edit: I'll take that back. I have heard some really great sounds out of movie mixes but I'm not going to make them 16bit and compare...

 

[441879]

Great thread folks. I didn't read every post, but definitely enough to convice me that the limitations on my system have nothing to do with bit rates. CD quality recordings, properly mastered, are good enough for my 50 year old ears and if I want better sound I should spend more on my headphones.

 

[KeithEmo]

Absolutely. I've heard enough regular CDs to demonstrate that they can sound remarkably good. The sad part is how many of them fail to live up to that level of sound quality.
 
Quote:

Great thread folks. I didn't read every post, but definitely enough to convice me that the limitations on my system have nothing to do with bit rates. CD quality recordings, properly mastered, are good enough for my 50 year old ears and if I want better sound I should spend more on my headphones.