Manual

81 DeepMind 6 User Manual
8.5 VCF
The VOLTAGE CONTROLLED FILTER (VCF) is an advanced lter designed specically
for the DeepMind 6. The VCF lter changes the tone color created by the OSCs and
NOISE generator by cutting o, or emphasizing frequencies/harmonics. The VCF
stage allows the low frequencies to pass, and cuts o higher frequencies. This
approach is used by many classic subtractive synthesizers.
The VCF is a fully analog lter, with the ability to be switched from a 2-pole/12 dB
per octave lter to a 4-pole/24 dB per octave lter. The dB per octave refers to the
angle of the lter's slope/response curve.
The VCF also has adjustable resonance which creates a narrow peak around the
lter cut-o frequency. The DeepMind 6 lter is capable of being driven into self
oscillation when the resonance setting is high. Unlike many other synthesizers,
the DeepMind 6 is capable of accurate pitch tracking even when the lter
resonance is pushed to (and past) the point where the lter starts to self-
oscillate. The self-oscillation is tuned so that you can play it as a fully polyphonic
3rd oscillator across the entire range of playable notes.
The VCF can be modulated dynamically by the VCF Envelope, LFO or Keyboard
Tracking. The VCF Frequency is also available in the Mod Matrix as a destination
where it can be modulated from any of the Mod Matrix sources.
8.5.1 VCF FREQ FADER
• The VCF FREQ fader controls the cut-o frequency of the VCF. The VCF will
begin cutting frequencies below the cut-o frequency and continue to cut
them at a rate depending on the number of poles used.
You can use the lter to sculpt the sonic characteristics of the OSCs and noise
generator, or you can dynamically adjust the fader to create sweeps of the
lter which will create distinctive movement.
Modulating the cut-o frequency with sources such as an envelope
generator, with fast attack settings can help emulate the attack transients of
natural instruments, or be used to creative eect.
The diagram below shows the results from high, medium and low settings of
the cut-o frequency when applied to the SAWTOOTH and
SQUARE waveforms.
The VCF FREQ range is from 50.0 Hz to 20000.0 Hz. The default VCF
FREQUENCY setting is 20000.0 Hz (fully open).
The fader position, current value and stored value for the VCF FREQ fader is
shown on the PROG screen. There is also a visualization of the lter curve as
shown below.
LEVEL (dB)
FREQUENCY (Hz)
HIGH
SAWTOOTH SQUARE
MED
LOW
VCF FREQUENCY
LEVEL (dB)
-3 dB
FREQUENCY (Hz)
LEVEL (dB)
-3 dB
FREQUENCY (Hz)