VCF
The VCF is an 18 dB low-pass filter with an adjustable resonance. It can be used to
increase or reduce the harmonics in the VCO's output signal. It features controls for
cutoff, resonance and envelope modulation:
n
n
The CUTOFF control determines the cutoff frequency of the VCF. Harmonics above
the cutoff frequency are clipped; all overtones below the cutoff frequency pass the
VCF unchanged. The range of the cutoff control has been designed to ensure that the
VCO does not modify signals when it is at its maximum position. In the minimum
position, virtually all harmonics are suppressed.
The RESONANCE control boosts harmonics around the cutoff frequency. When the
control is to the left, the harmonics remain unchanged. Turning the control clockwise
increases the resonance.
Note: The RES ADJUST trimmer on the rear panel of the MB 33 II can be used to
set the maximum resonance, i.e. the resonance level available when the
resonance control is turned all the way up.
n
The ENV MOD control determines the intensity with which the envelope generator
(ENV) modulates the cutoff frequency.
Envelope generator (ENV)
The envelope generator (ENVELOPE) generates a control voltage that can be used to
modulate the cutoff frequency (ENV MOD control) and the pulse width of the square wave
(the VCA features a separate envelope generator with a fixed voltage characteristic). This
control voltage is generated every time a new note is received, but not when the
AUTOSLIDE function is enabled (when more than one note is being played at the same
time). The position of the DECAY control determines the speed with which the envelope
voltage drops.
10
SINE MB 33 II (English)
