Doepfer A-120v 24dB Low Pass Vintage Edition (black)
Module A-120 is a voltage controlled low-pass filter, which
filters out the higher parts of the sound spectrum, and lets lower
frequencies pass through. The Cut-Off Frequency determines the
point at which filtering takes effect. You can control this
manually, or by voltage control (filter modulation, for instance by
an LFO). Three CV inputs are available, and the sum of the voltages
from these affects the filter cut-off.
The module is based on a so-called "transistor ladder" design, with
a cut-off slope of -24 dB/octave, as in various Moog synthesizers.
That's what gives it its classic, legendary Moog sound.
Resonance (or Emphasis) is adjustable all the way up to
self-oscillation - in which case the filter behaves like a sine
For more detailed information please look at the English user's
Technical note: The module has been revised in 2009.
The single transistors have been replaced by so-called transistor
arrays which look like integrated circuits. But these are no "real"
integrated circuits but contain nothing but 5 matched transistors.
The new version of the module is still a transistor ladder based
low pass filter !
Width: 8TE / 8HP / 40.3 mm
Depth: 65 mm (measured from the rear side of the front panel)
Current: +30mA (+12V) / -20mA (-12V)