Korg Soundlink DRS OASYS PCI Patches & Effects Manual page 131

PCM
This control has extra smoothing on the DSP, to ensure zipper-free modulation. If
instantaneous modulation is desired (such as modulation via velocity), modulate
the Filter Mod section's Envelope control instead.
Resonance
0-100. Resonance emphasizes the frequencies around the cutoff frequency. At 0,
there is no emphasis, and frequencies above the cutoff will simply diminish
smoothly. At very high settings, the resonance can be heard as a separate, whistling
pitch. At medium settings, the resonance will alter the timbre of the filter, but will
not usually be heard as a separate pitch.
Envelope
+/- 100. The ADSR envelope can be used to control the filter cutoff frequency,
adding to or subtracting from the setting on the Cutoff knob. With positive
envelope amounts, the envelope will increase the cutoff frequency above the setting
on the Cutoff knob. With negative amounts, the envelope will act as if it is inverted,
decreasing the cutoff frequency below the setting on the Cutoff knob.
At 0, the envelope will have no affect. At +100, the envelope will open the filter all
the way at its peak, even if Cutoff is set to 0. At -100, the envelope will close the
filter all the way down at its peak, even if the Cutoff is set to 100.
Envelope amount affect on cutoff frequency
Key Tracking
Amount
+/- 100. This adjusts the filter cutoff as you play higher and lower on the keyboard.
At the center key (as set below), the cutoff will be exactly the value set by the Cutoff
OASYS PCI
+100
0
-100
Cobalt 4+
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