From:	Weiqi Gao <weiqigao AT a DOT crl DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: sound() function
Date:	Sat, 04 Dec 1999 17:30:48 -0600
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Pablo Parra wrote:
> 
> Do anybody know how i can get a list of notes frequencies for the
> function sound() of c?

Well, the middle C is 261.63 Hz.  The A after the middle C is 440.00
Hz.  In general, to go up one octave, multiply by 2, to go down one
octave divide by 2.  Each tone is a fixed multiple of the preceding
tone.  Since there are 12 tones in an octave, this multiplier, call it
lambda, satisfies "lambda raised to the twelveth power equals 2", which
put its value at 1.0594630943593.  Thus the D after the middle C (2
steps, C->C#->D) is 261.63 * (1.0594630943593)^2 = 293.66 Hz.

Homework: Write a C program to print a frequency table from C0 to C8.

Note that this is the physics definition, the music industry has their
own ideas of how to place the frequencies to make each one sound good.

-- 
Weiqi Gao
weiqigao AT a DOT crl DOT com

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