Tube synth diy

I didn't even know about this group until Andrew told me about it.

Very nice. I take it you guys have looked thru all those old circuits
in the files section. And no doubt, somebody built some of them, and
found them to be lousy performers or otherwise rather useless for
electronic-music applications. The analog computer circuits that claim
to implement square, square root, exponential etc. functions tend to
be too inaccurate or flaky to use in a CV synthesizer. I found that
out 10-15 years ago--by actually building and testing a lot of that stuff.
What little "prior art" in this area is very limited, and you keep
seeing the same designs cited over and over.

The Judd book is your best bet, and even it is rather limited.