[sdiy] "Curtis" filter in Prophet 8

[Antti Huovilainen]

On Wed, 22 Jul 2009, David Ingebretsen wrote:

> While not strictly DIY, I am curious if anyone knows anything about the
> Curtis low pass filter in the Dave Smith Prophet 8 synthesizer? Is it using
> Curtis chips or did they re-do the circuit with discrete components?

My guess is CEM3396, which is basically two half DCos, VC mixer, 
CEM337x/338x style filter (similar to OTA even if internally implemented 
with some shortcuts) and a final VCA.

Antti

"No boom today. Boom tomorrow. There's always a boom tomorrow"
   -- Lt. Cmdr. Ivanova