Found a Zapp site, sadly Roger is dead, we won't likely find out what he was doing. He did however produce an album and a song to the effect of 'I play the talk box'...so he was using one after all. They're not that obtrusive if you wrap the tube round the mic stand...It would still be interesting to play with formant sounds in FM; I think it could be convincing if set up right, but if money were no object I'd just MIDI the 100 into a FS1X module, that seems to be what they're for. I'll be dusting off the DX7.mn