Vermona PERfourMER MKII - quad analog synthesizer - Manual (Page 12)

Filter Section (VCF)
The filter shapes the oscillator's output signals, either one of the available
waveforms, the noise generator's output or an external audio signal. Certain
frequencies will be suppressed, resulting in subtle to significant sound
changes. Dynamic control of the filter will create progressive sound changes
over time.
Each of the PerFourMer MKII's synthesizer channels offers a voltage-con-
trolled resonance-capable low-pass-filter with a slope of 24dB per octave.
This proven effective filter-type has already been used in legendary synthe-
sizer-models developed by Bob Moog. A low-pass-filter allows frequencies
of an audio signal to pass below a certain frequency (cutoff frequency) and
suppresses all frequencies above.
The filter section has the following control elements:
Picture 2: The filter section
CUTOFF
This control sets the filter's cutoff frequency. This is the frequency from
which the audio signal is manipulated (filtered). Frequencies above the
cutoff will be attenuated with the filter’s slope. Setting the cutoff lower
will result in a more muffled sound as more harmonics are suppressed.
Beside manual control of the cutoff frequency, this parameter can also
be modulated and controlled by MIDI aftertouch or a corresponding MIDI
control command. This function can be enabled/disabled using EDIT
PARAMETER 3: AFTERTOUCH CUTOFF (VCF).
Owner's Manual VERMONA PERfourMER MKII
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