PC preferably

What do you mean by spectral inverting, data? If it is reversing the order of spectral components, i.e. putting high parts of the spectrum into low frequencies, and vice versa, a simple ring modulator with fmod=20kHz makes the trick.

Have you had a look at Prosoniq Pi-Warp? That might do what you want.

There is Spectral Mirror in the SoundTransformer plugin pack, but those are only available for Mac. Anyway, it's not quite so great because it inverts frequencies linearly rather than logarithmicly, so you get loads of high frequencies (basically everything below the highest octave moves into the highest octave) & very little else.

A few years ago, I wrote a Csound opcode that does spectral inversion logarithmically. It's basically just a modified version of pvadd. I've only rebuilt Csound for Mac, but I would gladly send you the source file if you know how to compile Csound for yourself. I would consider turning the effect into a VST plugin if I actually understood 10% of the phase vocoder analysis code involved, & if I thought that I could make it run anywhere close to realtime...

A Logorithmic Spectral inverter sounds cool. I don't like CSound though, someone really needs to re-write that prog, it's well out of date.

Isn't Pi-warp just some kind of frequency shifter with a built in LPF and reverb?

Yeah, I agree about Csound, I never use it anymore, even as much as I love my spectral inverter & have no other way of doing it... In fact, the phase vocoder analysis is a good example of how out of date Csound is. It's completely impossible to use any of the pvoc opcodes in realtime because you have to record an audio file, run it through the pvoc analyzer & render an analysis file, & then work with that analysis file in Csound. Yuck...

there is csoundAV(new version of realtime csound)
http://web.tiscali.it/G-Maldonado/download.htm
I believe it has pvoc and the newer streaming pvoc opcodes(i have no idea what the difference is)

Also richard dobson has made a realtime pvoc vst plugin
http://www.bath.ac.uk/~masrwd/pvplugs.html

I dont think they are really that interesting though. I think part of the problem is these processes dont seem to lend themselves well to a plugin. To me the interesting stuff comes from time varying parameteres which is rather hard to do with midi cc data. If the plug had absynth style envelopes that might be a different story but that would take some serious cpu cycles.

is this what you mean ?
http://vellocet.com/software/VSpectShift.html

Just to point out that a preliminary version of a VSTi version of CSound is available, as is one which will work as within MAX.

Although I'd most want to see it integrated into an audio editor for interesting sound-mangling.

Arrghh! That Vspectshift is nasty! They're right -logorithmic would be more musical (not to mention usuable!).

I'm aware of Supercollider. In fact, I went to a seminar on it once and I agree, it does look amazing. Unfortunately, it is for Mac users only

Max/MSP would also be a viable option and less time-consumeing, but it's taking an eternity for Cycling74 to release a PC version. I doubt I'll ever see it come to light in my lifetime

how sbout this one
http://www.ohmforce.com/products/pcat.php?pcat_id=4&PHPSESSID=84ae1993 85d7e7d9d2669763dee6c5e9

[ 16 April 2002, 21:22: Message edited by: realmarco ]