Mike Raiford wrote:

> Silly, I know. The scaling seems right, but just sort of. Editing in the 
> frequency domain makes the time domain really big.. :/

If you add lots of waves together, the resulting wave is very large. 
Normally waves containing lots of frequencies have very little energy at 
each specific frequency, because it's so spread-out.

> Next: write an FFT filtering algorithm and export the resulting wav.

Good luck! ;-)

> If you set the 
> tones to the fundamental, then 1x 2x 4x etc ... it sound exactly like 
> an organ.

Yes. I myself have in fact used this in a musical composition. I wrote a 
small BASIC program that generated various waveforms, and then used 
OctaMED to play tunes with them.

Thinking about it... one technique frequently used in real organs is to 
play several stops at once, each tuned to some octave of the 
fundamental. (I.e., a power of two of the frequency.) If you assume the 
tone of each pipe is approximately a pure sinewave, this is what you get.

> if you do 1x 3x 5x 7x setting each subesequent to half, you 
> get an approximation of a square wave.

Assuming the amplitude is the reciprocol of the frequency, yes. This is 
the Fourier series of that waveform.

> 1x 2x 3x 4x, again half each, you get an approximation of a sawtooth wave.

Again, yes.

Also, if you take the square wave, make the amplitude the reciprocol of 
the *square* of the frequency, and make every other wave shifted 180° 
out of phase, you get a triangle wave.

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