Non LPF ladder filters?

Mark Smart smart at
Tue Dec 19 16:56:53 CET 1995

> There's the voltage-controlled phase shifter on the ARP Quadra.  It's
> an incredibly clever variation of the Moog ladder.
>   -- Don

Absolutely! I've got schematics for this, because I'm repairing my friend's
Quadra. It has, get this, FOURTEEN STAGES. Every two stages on a phase
shifter creates a notch in the spectrum, so it makes SEVEN notches. For
comparison, most commercially available phase shifters have four stages
and produce two notches. This things sounds really incredible when you
use it on the Quadra's string section. Wow. I can copy the schematic for
you if you're really interested.

*     Mark Smart                               *
*     Network Technician                       *
*     University Communications Inc. (UCI)     *
*     smart at                      *

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