[sdiy] New take on VC moog ladder

[mikko.a.helin at nokia.com]

Magnus, what's a problem with the Q13? Anyway, could the LM13700 internal
darlington buffers be used instead or can the 13700 OTA really source the
cap and <1k input of Q3&Q4 without any buffering? The output stage at least
could be buffered? Paul's previous version of this was strange as it
actually tried to use the Walt Jung design, wasn't it?

-Mikko

> -----Original Message-----
> From: ext Magnus Danielson [mailto:cfmd at swipnet.se]
> Sent: 21. December 2001 1:03
> To: Paul.Maddox at wavesynth.com
> Cc: synth-diy at dropmix.xs4all.nl
> Subject: Re: [sdiy] New take on VC moog ladder
> 
> 
> From: "Paul Maddox" <Paul.Maddox at wavesynth.com>
> Subject: [sdiy] New take on VC moog ladder
> Date: Thu, 20 Dec 2001 20:25:45 -0000
> 
> > Dear all,
> > 
> >  Ok, how's about this....
> > 
> > Http://www.modulus.wavesynth.com/projects/CV_MOOG_VCF_2.pdf
> > 
> >   I've kind of cheated a little :-)
> 
> A little?????
> 
> You *badly* want to buffer your taps of that capacitor. You want a
> JFET thingie to buffer up. Toss a TL072 on that...
> 
> Do you really want all that Q13 stuff?
> 
> > The LM13700 CV PNP transistor bit taken from the moog 
> source/memory moog
> > (thanks colin/tony)
> > 
> > Workable?
> 
> TRY it. You'll probably learn something usefull that way.
> 
> Cheers,
> Magnus
>