VCF: Voltage Controlled Filter
The low-pass filter shapes the tone by selectively filtering cer-
tain parts of the harmonic spectrum of the sound generated
by the Oscillators and the Noise generator.
This knob is used to set the cutoff frequency. Harmonic con-
tent above the cutoff frequency will be filtered out.
Turning the knob to the left will lower the cutoff frequency,
and turning the knob to the right will raise the cutoff frequen-
If the CUTOFF value is set too low, the volume may
be extremely low.
Also known as Peak or Q, the RESONANCE control adds additional emphasis
to the overtones occurring at the CUTOFF frequency, giving a distinctive char-
acter to the sound.
Turning the knob to the right will increase the resonance effect.
Low resonance value
The overtones that are emphasized will change depending on the cut-
off frequency. For this reason, it's good to adjust the CUTOFF knob
while adjusting the RESONANCE knob.
When emphasizing the overtones in this way, the sound may distort
depending on the cutoff frequency or the input audio.
High resonance value