Filter - CreamWare PRODYSSEY ASB Benutzerhandbuch

Audio Mixer
This is where the signals are mixed before they
get sent to the filter. You can choose up to three
of the six signals and adjust their volume levels.
Possible signals are noise or ring modulation of
OSC1&2, sawtooth or square of OSC1 and saw-
tooth or square of OSC2.
Filter Section
The filter section consists of a modulatable low-pass filter with
resonance and is followed by a non-resonant, frequency-adjusta-
ble high-pass filter. Each knob can be toggled between "Prodyssey"
(ARP 24-dB low-pass filter with a cutoff at around 12 kHz) and
"Minimax" (Moog 24-db low-pass filter, a legendary Moog cascade)
– a powerful feature that the original did not have. The low-pass
filter determines not only the envelope and other modulations but
also the shape of the sound curve. Frequencies below the cutoff
frequency are not processed, hence the term "low-pass"; frequen-
cies above the cutoff frequency are attenuated by 24dB/octave.
Resonance is a result of feeding back the filter output to the filter
input, thereby amplifying the frequencies near the cutoff frequency.
The circuit modeling process enables both filters to emulate the
characteristics of the original. The cutoff settings and the reso-
nance behavior illustrate the typical ARP and Moog characters. The
high-pass filter that follows the low-pass filter works without reso-
nance and modulation. Frequencies above the cutoff frequency are
not processed, hence the term "high-pass"; frequencies below the
cutoff frequency are attenuated by 6dB/octave.
14