Hi Jamie,

> I'm looking at putting together very compact Doepfer system...around
> 4-5 modules...and wondered what the physical depth of the Doepfer
> modules is

It varies quite a bit. I've just Done a quick check on some of the
more obvious ones that you might use: A-110, A-140, A-121/122/123, A-
138, A-130/131, and they are all less than about 2 1/2 inches.
Without popping them all out, the biggest I can think of (from
memory, of those I have...) are the A-126, about 4 1/2 inches deep,
and the A-190 at about 4 inches deep. If you know roughly what you
are thinking about, and I have got them, I can easily pop them out
and let you know!

Tim