i have a general idea of what they are , but does anyone know *exactly* what they do ? or can give specific examples ? also , anyone know any software versions of one ?
Vocoder technology has actually been around for quite a while ('60s or 70's I think). Recently made popular by Cher's song "Believe" ... a vocoder is an effect that allows the user to "vocalize" a wave form. Probably the most widespread application has been the guitar Heil Sound talk boxes that were used by Peter Frampton, Joe Walsh, Steve Vai and many others. These effects basically take the output of a guitar amp and pump it through a tube that the user puts in his/her mouth to make the sounds.
Basically, vocoders are used to take a straight sound (from synth, guitar, computer, etc.) and make it 'sing' or 'talk'. The applications for this effect are not limited to music or recording alone. The telecommunications industry uses this technology a lot. Especially wireless telecommunications.
I'm not sure if she used a vocoder or not, but Urszula Dudziak sang through some weird bank of synthesizers with Michal Urbaniak's
band and on her own albums. Semi-synthetic scat would be the closest description I can muster. Definitely worth checking out.