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Subject: Re: [motm] Re: OT: Tales from an Audiophiles Crypt

From: Tim Walters <walters@...>
Date: 2002-10-30

>That's already a given, and you missed my point anyway. If you sample a
>sine wave @ 20Khz and a square wave @ 20khz, you will only get a 10khz
>square wave when you go D to A. The sine wave will lose detail.

No, it won't. That's the whole point of the Nyquist theorem.
Everything below the Nyquist frequency is reproduced ∗exactly∗ (given
ideal filters etc.). A 20kHz sine wave is just as detailed when
sampled at 44.1kHz as when sampled at 96kHz; either way, it contains
all the information of the original wave.

The only thing increasing the sample rate does is allow you to
represent higher frequencies (and possibly to design a better
real-world filter).

>I don't know what "statement" you're referring to, other than the quality
>of the waveform has zip to do with the Nyquist Theorem.

That would be it.
--


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Tim Walters : The Doubtful Palace : http://www.doubtfulpalace.com