Audio Damage BigSeq2 - Manual (Page 16)

Filter
The Filter effects block contains a filter (not surprisingly) with several
different modes. The FREQ controls the cutoff frequency of the filter. Rotate
the knob clockwise to increase the cutoff frequency.
The RES knob controls the resonance of the filter. As the resonance of a
filter increases, the filter's output emphasizes frequencies near its cutoff
frequency. In plainer terms, if you turn up the resonance knob, the filter
sounds more “synthy”. (Try it—you'll hear what we mean.) If the filter type
is set to 4P LP (see below) and you turn the resonance knob fully clockwise,
the filter will oscillate, producing a sustained tone even if the plug-in has no
input signal. Some of BigSeq2’s presets, such as “Self Osc Acid”, use the
self-oscillating filter to turn BigSeq2 into a mini sequenced synthesizer.
The TYPE knob switches the filter between several different filter models. As
you rotate the knob, watch the knob’s display to see which filter type is
active. The available types are:
 Four-pole low pass (shown as “4P LP” in the parameter display) –
the filter type most commonly found in synthesizers. A low-pass filter attenuates or reduces signal
frequencies greater than its cutoff frequency and passes signal frequencies below its cutoff frequency
without alteration. As you rotate the frequency knob clockwise, the filter passes more of the signal's
high-frequency content and the output sounds brighter. If you turn the frequency knob fully counter-
clockwise, you may not hear any output at all because the entire signal has been filtered out.
 Three-pole low pass (shown as “3P LP”): A low-pass filter with a frequency roll-off curve that is less
steep than that of the four-pole filter. Three-pole filters are fairly uncommon, but the three-pole low-
pass filter found in a certain bass-line synthesizer defines entire genres of electronic music.
 Two-pole low pass (shown as “2P LP”): A low-pass filter with a frequency roll-off curve that is less
steep than either the three-pole or four-pole low-pass filter. Two-pole filters are usually used for
gentler frequency-shaping applications, such as in equalizers or tone controls, but are found on some
synthesizers.
 Four-pole high pass (shown as “4P HP”): A high-pass filter works in a manner opposite to that of a
low-pass filter: it reduces signal frequencies less than its cutoff frequency and passes signal