Phil Leigh;381160 Wrote: > The link doesn't work ... is it this one? > http://en.wikipedia.org/wiki/Information_theory > > If so - yes I have read it.
Sorry. Nope, I mean the "Practical Implications" section of this one: http://en.wikipedia.org/wiki/Sampling_(information_theory) In short, I agree with you wholeheartedly that 44.1 captures all the salient information of a band-limited (20-20khz) signal. No doubt about it. The key point that I'm trying to make is that it is not possible to implement the necessary anti-aliasing and reconstruction filters in a sonically-transparent way. We cannot build "clean" filters steep enough - 96dB down immediately for 16-bit data (24-bit is worse). Phase effects alone are large. These filters are very possible at 88Khz or above. Phil Leigh;381160 Wrote: > what "intersample effects"? Do you think there is information (different > sample values) missing. There isn't. If there were, the Shannon et al > are completely wrong. They are not wrong. We just can't engineer the filters necessary to make their math "real." Phil Leigh;381160 Wrote: > This is easily proven. Record something with no or very little energy > above 20kHz at 96/24 and downsample it properly in software to 48/24. > Compare the two versions in a blind test on good equipment. They sound > the same. Even better, record an analogue replay of the two versions > using a 96/24 ADC and compare the captured files...hmm - identical. > Why? - because there is no extra information captured at the higher > sampling rate. Fair enough. I do not believe that the two files would be bit-perfect correct, but - as I have said before - the blind listening test may be challenging! <g> Phil Leigh;381160 Wrote: > I wouldn't dream of telling you or anyone what you are and aren't > hearing! Only your brain can do that. > > I would however urge you to try the tests with an open mind. I have > several friends who confidently told me that they could detect a > difference between some 96/24 Linn Masters and the same downsampled to > 48/24... until we did the blind test and they failed miserably :o). I > failed too... Believe me, my mind is open, and you make excellent points. It would be quite nice for me and everyone else if 16/44 sounded as good as 24/88 (or above). But in my opinion, it doesn't. I will also point out that another key variable is in play besides sampling rate - bit depth! I must confess that I have not done tests at, say, 16/96. But one day I shall. -- teros ------------------------------------------------------------------------ teros's Profile: http://forums.slimdevices.com/member.php?userid=18601 View this thread: http://forums.slimdevices.com/showthread.php?t=57631 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
