[sdiy] How does 3320 sound as hipass/bandpass

[TooManySynths]

> 2) The Xpander/M12 uses the 3372 and it is
> multimode. 
> Does the xpander circuit use the 3372 in a multimode
> mode?  Can someone point me to some 3372 designs?
> Can
> someone point me to the M12/Xpander filter
> schematic?

Ok, I now have the ob12 voice schematic. The sixteen
modes of the xpander are obtained via the gain cell
access points of the 3372.  Now, please understand
that I don't know enough about OTA's or filters to
really understand why this works.  But, since I own an
M12, I'm sure that it does.

So, my next question is, has anyone tried this idea
with other filter chips?  I think the anderton insane
filter does something simmilar, although, the oberheim
design is pure elegance.  Frankly, I can't imagine
that it wouldn't work.  I expect however, that the
passive part values are not casually chosen so it's
not guarantee that a chip that is considered superior,
i.e. the 2044, would be so in such a configuration. 

At the very least I plan to build an Xpander filter
for my modular.  I'm just drooling at the thought. 
I've always liked the 3372, in fact, I like most of
the CEMS, just not the 3320. In addition, I'm going to
try other experiments tapping the gain cell access on
other filter chips and see what results I obtain. 



Daryl


__________________________________________________
Do You Yahoo!?
Get email alerts & NEW webcam video instant messaging with Yahoo! Messenger
http://im.yahoo.com