A-105-4 is our first polyphonic filter and contains four
identical 24dB Lowpass filters (SSM2044 type). It has
available common manual controls and CV inputs with
attenuators for these parameters:

Frequency (F)

Frequency Modulation Intensity (FM)

Resonance (Q)

Audio Input Level (L)
Each filter has available a separate FM input as well as
an Audio Input and Output. The FM input is typically
connected to the output of the associated envelope
generator (e.g. A-141-4). The envelope amount for all
four filters is controlled by the FM knob and the CVFM
input by means of four built-in VCAs, which are
controlled by the FM control and CVFM input. This
allows also voltage control of the envelope amounts.
In addition common frequency modulation for all filters
is possible (e.g. by an LFO). For this the CVF input
with attenuator can be used.
The range of the audio input level control (L) allows
also clipping/distortion with typical A-100 audio levels
(e.g. from A-111-4) at the filter inputs. Even this
parameter is voltage controllable as well as the
resonance (Q).
Application: polyphonic patches (four VCFs with same

  • ? mA +12V
  • ? mA -12V
  • ? mA 5V

This Module is a prototype or in a concept phase.

8 HP FilterQuad
submitted Jan 22nd, 09:20 by cds | last Change Mar 9th, 18:31 by Tycosqr

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