Kurzweil K2000 - MUSICIANS GUIDE Musician's Manual page 260

DSP Functions
Filters
The Coarse Adjust parameter sets the cutoff frequency in terms of a key name. The remaining
parameters (except Pad) alter the cutoff frequency in increments of cents. YouÕll notice that
positive values for key tracking have an interesting effect on the function of lowpass Þlters;
positive key tracking values raise the cutoff frequency for high notes and lower it for low notes.
More speciÞcally, a value of 100 cents per key on this page, when Þltering a constant waveform
like a sawtooth, would result in waveforms of exactly the same shape for all pitches of the
waveform. The cutoff frequency moves in sync with the frequencies of the waveformÕs partials
as different pitches are generated. Negative key tracking values will steepen the rolloff of
lowpass Þlters above the cutoff. The Pad parameter, as always, attenuates the signal at the
input to the function. These parameters affect all the lowpass Þlters similarly.
Two-pole Lowpass Filter (2POLE LOWPASS)
The two-pole lowpass Þlter has a rolloff of 12 dB per octave above the cutoff frequency. This is a
two-stage function, so it has two control input pages. The Þrst affects the cutoff frequency, and
has the same parameters as the one-pole lowpass. The second control input page (F2 RES)
affects the resonance of the Þlter. Resonance is a cut or boost in amplitude of the partials in the
vicinity of the cutoff frequency.
Set the resonance with the Adjust parameter on the F2 RES control input page, and use the
other parameters to assign various controls to alter it. If a boost is applied at frequencies where
there are high-amplitude partials, the signal may clip. The Pad parameter on the F1 FRQ page
will reduce the clipping, but thereÕs no harm in keeping it if you like the sound.
EditProg:F2|RES(2P|LOPASS)|<>Layer:1/1||
Adjust:0.0dB||||||||Src1||:OFF||||||||||
||||||||||||||||||||Depth|:|0.0dB|||||||
||||||||||||||||||||Src2||:OFF||||||||||
KeyTrk:|0.00dB/key||DptCtl:OFF||||||||||
VelTrk:|0.0dB|||||||MinDpt:|0.0dB|||||||
||||||||||||||||||||MaxDpt:|0.0dB|||||||
<more||F1|FRQ|F2|RES|F3|||||F4|AMP|more>
PARAMETER
14-8
10 100
20
0
-20
-40
-60
Cutoff frequency at C 5;
resonance from -12 to 24 dB
in increments of 6 dB
-80
Frequency in Hertz
1000 10000
24
-12
RANGE OF VALUES
100000