[vorbis] 24/96 ?

[medit]

MARK JAMES HETHERINGTON wrote:

 > This sampling issue mentioned below is the only reason I can see 96Khz
 > sampling being useful. But keep in mind that this only occurs when the
 > waveform is very close to a multiple of 44.1Khz, so really only above
 > 20Khz are affected greatly.

<p>Not exactly true. If you've got a signal that's slightly
out of phase with a multiple of the sampling rate then
what you sample will be a sine wave at a much lower
frequency than the actual signal. This is the definition
of "aliasing" - one frequency pretending to be another.
This is shown (let's see, google, google, google) here:

http://www.medicine.mcgill.ca/physio/vlabonline/biosiglab/aliasing.htm

<p> > ... Most people can't hear above 16Khz anyway,

 > and I think you only really need to allow up to 20Khz. 22Khz is a
 > stretch for most peoples ears. 96Khz takes us into the realm of
 > overkill,

<p>High sample rates are mainly needed to avoid aliasing,
not to reproduce the signal any better (though they can
do that as well!)

<p><p><p><p>
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