Harry Bissell Envelope Follower

[Jason Stout]

Lately I have been foolin' with envelope followers and realize that I won't be able to beat Harry's circuit. Before I do a PCB layout, I thought I'd try to save myself some time. Has anyone made a layout?

The circuit can be seen here:

http://www.reed-electronics.com/ednmag/article/CA265499?pubdate=12%2F26%2F2002&spacedesc=designideas

[Mark Hammer]

You can always write to Harry and ask him if he has a layout he'd mind sharing.  Bear in mind that he designed expressly for his own hex-pickup guitar processor/synth, so while he may have a layout that he'd be willing to share (and I'm guessing on that part, but I know for a fact he's a nice guy), it may well be for a hex-follower implementation that doesn't easily lend itself to dividing up into 6 discrete units.  Remember the Schitt trigger chip that clocks the three submodules is a *hex* unit, hence likely shared across the six individual strings in his unit.

I will say, though, that having played the guitar this thing is connected to, I can't recall an envelope follower that was as responsive and trouble free in my experience.