Exactly, you wire a connector for External VCF CV, if you add a rectifier with a voltage
double you will be able to input audio from an audio interface or any other audio source
and the rectfier will convert the audio signal in control voltages, I tried it here and it
worked but it seams to add some kind of distortion, maybe it's a side effect of the
voltage doubler, it works perfect for Silent Way but as an envelop follower it acts
strange, you could try an input that only have a rectfier, a full wave rectfier could
work.
Ah, I think I get you now, Bill: I was thinking External Audio as "WAV" for instance into the FM Cutoff CV IN, which doesn't work, right?
Instead, I should think in terms of External CV In into the FM Cutoff CV In, is that it?