Well after starting this branch of the thread I went down and plugged
in all my VCOs to a scope and they all lack in "perfectness" from the
true waveshapes. I used to teach electronic music back in the 70's
with an Arp 2500 and those old synths had great waveforms if I
remember correctly. And you could keep tacking on CV sources to them
without them sagging and needing buffer amps etc. too. I have AS and
Doepfer analog modules and they all show mis-shaped waveforms from the
true shapes. The talk on this list about one VCO sounding better/worse
than another makes sense for the first time now! I come from a era
where one VCOs waveforms were closer to another's and the differences
were mainly in the tracking and features.
The best analog sine shape I found in my rig was the Doepfer
quadrature VCO and one of the Doepfer LP filters in resonance
feedback. Other than that the best waveform shapes came out of one
piece of kit I own. All of them the expected textbook shapes. As
heretic as it may sound - theses came from my Nord G2. I would have
guessed that though since it is easier to make them from a look-up
table than from circuits.
Please - no Digital vs. Analog religious wars because of that - We
have ALL been there and heard it all already.
-James