source file: m1560.txt
Date: Wed, 21 Oct 1998 18:31:51 -0400

Subject: Re: Cancelling out beats

From: "Paul H. Erlich" <PErlich@Acadian-Asset.com>

Bram wrote,

>I have a somewhat better idea of what I mean by 'beats' now. If take
the
>volume of a sound wave (I forget the three letter acronym off the top
of
>my head)

RMS?

>and express it as the sum of a bunch of volumes of individual
>sine waves, (no, I don't know a simple way of doing that
transformation)

Is it unique?

>the beats are the waves in the resulting summation which weren't added
>together to get the original waveform.

Sounds like you're talking about interference, which is a much more
general phenomenon than beating.

>I think making a sound whose timbre is a bunch of pure tones is even
>easier - just take the derivative of the square root of the sum of
their
>squares, but that just seems *too* easy.

I don't understand what you mean by that, but any sound can be expressed
as a (possibly infinite) bunch of pure tones.