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

From: "J.D. McEachin" <jdm@...>
Date: 2002-10-30

On Tue, 29 Oct 2002, Neil Bradley wrote:

> 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.

No, you get a 10kHz SINE wave, due to the reconstruction filter following
the DAC. That is, IF the filter is ideal, as specified by Nyquist.
Since no real world filter is ideal, in reality you'll get some of the 2nd
harmonic at 20kHz.

JDM