[vorbis] 24/96 ?

[MARK JAMES HETHERINGTON]

I should have noted "I am not a signal aliasing expert!" Sorry.

<p>----- Original Message -----
From: medit <meditvr at teleline.es>
Date: Thursday, December 20, 2001 9:13 am
Subject: Re: [vorbis] 24/96 ?

> 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.
> 
> 
> 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
> 
> 
> > ... 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,
> 
> 
> High sample rates are mainly needed to avoid aliasing,
> not to reproduce the signal any better (though they can
> do that as well!)
> 
> 
> 
> 
> 
> -- 
> <\___/>
> / O O \
> \_____/  FTB.
> 
> 
> 
> 
> 
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