UPDATE: (to be updated with audio examples soon)
UPDATE: (I'm not sure if these are legal to use for IronChefOfMusic remixes, since they may be completely resynthesizing the source ingredients without actually using the ingredients in the resulting output.)
Using my vastly limited knowledge and half-assed-internet-research, here’s some information about PHASE VOCODERING (PVOC), and a list of my favorite VST plugins that use it.
First (a long time ago) I wanted to know how some of the odd sounds were created for use in Aphex Twin’s Windowlicker and surrounding singles/albums. They had elements with a corrupt low-bitrate MP3 squishy sound, applied in a deliberate way.
I performed a bit of searching for audio plugins based on terms like “window”-licker, spectral, FFT, and vst. Being a long time Cooledit user, I assumed there was some form of FFT based filtering going on, and it was the “spectral” view of the other track on the Windowlicker single that exposed the encoded scary face. Also, at the time, I was often coming across anecdotes of how the CDP (Composers Desktop Project) was something amazing, but reserved for idiot-savant-csound people with pony-tails and math degrees.
This led me to a page with free (32bit) PVOC vsts that demonstrate the fundamentals of what phase-vocoding can do.
I’m surprised the page is still online, so here:
The gist is:
- PVACCU: spectral accumulation. The most extreme effect of the three! Applies feedback echo to each analysis channel, with the possibility also to apply a pitch glissando up or down. Echo is amplitude dependent, so this effect is most apparent when applied to percussive sounds, or any sound with distinct changes.
- PVEXAG: exaggerates the spectrum. Positive exaggeration will emphasize spectral peaks, eventually becoming distinct pitches. Negative exaggeration flattens peaks, and larger values will effectively generate a granular noise. This can sometimes be effective for some percussive sounds, such as drum loops.
- PVTRANSP: an unsophisticated pitch shifter, offering a range of one octave up and down. Really little more than a demo of the fact it can be done at all!
Some additional free and not free plugins to try:
Fragmental is a multi-effect, but about half of them use the three aforementioned PVOC expressions.
I think this is the most familiar one to most people. It’s also a multi-effect, and takes a bit of effort to wrangle all the parameters to use with intent.
Soundhack pvoc kit
I actually haven’t tried these yet since they aren’t free, and are a little pricey, but I'll give them a shot soon.
One issue to note about all PVOC plugins I have tried is that if your DAW supports automatic plugin delay compensation, you may notice quite a delay by the time audio reaches your master output.