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Phase Vocoder Appreciation Thread

#1
Ok... So I've been messing around with digitally assissted music for quite a while (5 years or so), and, tho I don't make the best tunes around (yet), I have learned, and perhaps pioneered some pretty amazing techniques.
I'm gonna share a little bit of that knowledge here.

What the phase vocoder (as I learned it) does is it splits a given sample of sound into it's seperate component frequencies. (Kinda like a prism) This is accomplished through a lengthy multiplication of sines and cosines. This is done in 'windows', meaning the sample is cut up into little chunks of time before being spectrally anayzed. The resulting data is a set of spectral data, basically stating the strengths of each frequency at a given point in time. This data can then be recombined, using what is basically additive synthesis.

The major selling point of this technique is the seperation of time and pitch. Like timestreching/pitchshifting, you can now change the pitch of a sound without changing the tempo. (Or vice versa) However, this can now be done fluidly + dynamically, instead of applying the changes to the whole sample. For example, you can modify the pitch of a break using a slow sine wave over time for a very cool effect.

There is also a much lesser chance of introducing artifacts when transforming the sound. This means you can be more 'extreme' when pitchshifting or timestreching your beats.

Another cool effect is using a different waveform than a sine for resynthesis. This will transform things almost beyond imagination; give it a shot.
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