User Manual

20 Filter Dave Smith Instruments
Filter
The Filter takes the basic, raw sound of the oscillators and noise genera-
tor and subtracts frequencies, changing the harmonic content and char-
acter of their sound. This change can be varied over time using the Filter
Envelope to produce more dynamic, animated timbres.
The OB-6’s lter is a 2-pole, 12 dB per octave, analog, state-variable lter
with low-pass, notch, high-pass, and band-pass modes.
The lter mode knob sets the lter’s mode of operation. It transitions
smoothly from low-pass to notch to high-pass operation, allowing a
blending of these modes. Band-pass operation is selected with the BP
switch. Each lter mode has its own characteristic sound and function:
• Low-pass: passes frequencies below the cutoff frequency
• Notch: removes frequencies in a notch centered around the cutoff frequency
• High-pass: passes frequencies above the cutoff frequency
• Bandpass: passes a band of frequencies centered around the cutoff frequency
Band-pass mode is selectable only through the bp on/off switch. However, you
can actually smoothly transition between normal and band-pass operation by choosing
norm-bp as a X-Mod destination in the mod matrix.
RESONANCE
TRACK
HALF FULL
BP
FREQUENCY
NO TCH
LP HP
FILTER
The OB-6 Filter