[sdiy] Moog VCF: Taurus vs. "Regular"

sleepy_dog at gmx.de sleepy_dog at gmx.de
Thu Mar 24 19:52:42 CET 2016

Hey there,

I recently stumbled upon some EFM circuits, such as their version of the 
Moog Taurus VCF.
It is nicely low-parts count compared to the "regular" (MiniMoog, 
Source, ...) VCF.
The main difference I spot is that in the "regular" one, the two sides 
of the transistor ladder are bufferd by each an own opamp, of which the 
outputs each go into one of the inputs of a third opamp, used as 
difference amplifier.
In the Taurus, there's just 1/2 of a LM13700, with its voltage inputs 
connected directly to the left / right parts of the ladder, and the 
current input fed by a fixed resistor going to one supply rail.

I guess the Taurus needed low parts count for it's a pedal.
And also, it's a bass pedal, which makes me wonder...

Does the Taurus VCF setup suffer from any sonic / performance 
disadvantages over the regular Moog VCF? Or would it do just fine in a 
synth not strictly for bass sounds?


More information about the Synth-diy mailing list