[sdiy] Discrete OTA

[David G Dixon]

> Incorporating the expo converter is handy, but the Osamu 
> Hoshuyama temperature compensation is a fairly compelling 
> argument for the 2164.

Yes it is.  That scheme is in every VCO I've ever designed, including the
Dixie, and Rubicon, and the Atlantis.

> To play devils advocate, I believe the SEM3320 used 
> conventional OTA's and made for a compact design, and no-one 
> complains about the sound of an OBX-a! 

Yeah, actually, my first 24dB cascaded-stage filter sounded really nice with
OTAs.  It just is so much easier to use 2164.