Wiardgroup

> Speaking of the Boogie - since it is "so moog" sounding - how 
about a
> matching highpass filter?  That would be smokin' - a 300 
Series
> Lowpass/High Pass Boogie....

To make a highpass, you just switch the location of the caps and 
the Vactrol resistive elements. It can be done neatly on the 
existing PC board, but works better with the Silonix cells, rather 
than Hamamatsu (for mechanical reasons). That is one of the 
reasons there is copper for 4 individual cells in addition to the 
Hamamatsu duals.

The Moog 904 A, B and C setup was incorporated in the 300 
Boogie design. The top half is the A and B modules and the 
bottom 4 knobs are the filter coupler (904 C).

It violates the "no dead knobs" rule because, when the coupler is 
switched in, the coupler frequency control disconnects the 
individual frequency controls on both the lowpass and highpass 
sections. I guess one could add LEDs ala Buchla to show which 
controls are active in what mode.