Buchla Bandpass VCF

[Romeo_Fahl at stream.com]

"Grant Richter" <grichter at execpc.com> on 09/07/99 04:14:40 AM
                                                              
                                                              
                                                              
 To:      jorgen.bergfors at idg.se,                             
          Juergen.Haible at nbgm.siemens.de,                     
          synth-diy at mailhost.bpa.nl, urekar.m at EUnet.yu        
                                                              
 cc:      (bcc: Romeo Fahl/Beaverton/Stream)                  
                                                              
                                                              
                                                              
 Subject: Re: New Stuff                                       
                                                              







Susan Ciani made that particular input famous by using it to
synthesize the Pepsi bubbles for commercials.

The "slow response" is relative. While the 2C3s take
5 milliseconds or so for a three decade step change,
the small signal response has better bandwidth.

----------
> From: jorgen.bergfors at idg.se
> To: Juergen.Haible at nbgm.siemens.de; synth-diy at mailhost.bpa.nl;
urekar.m at EUnet.yu
> Subject: RE: New Stuff
> Date: Tuesday, September 07, 1999 12:53 AM
>
> >This is what I mean. Substituting opamps will most probably change the
> >bahaviour of the circuit.
>
> I'm not an expert at circuit theory, so excuse me if this is a stupid
question:
> Wouldn't it be possible to omit the FETs in the Buchla BP VCF when you
use FET input opamps like the TL071?
>
> Another question regarding this filter:
> There is an FM input that it AC coupled. This has a cutoff frequencu of
approx 7,2 Hz (47k, 470n). But with the slow response of the Vactrols, how
useful is this input?
>
> /Jorgen