Kurzweil K2661 Musician's Manual page 517

Two-pole Bandpass Filter (BANDPASS FILTER)
This is essentially the opposite of a notch filter; it passes all partials at the center frequency, and
cut the levels of partials above or below the center frequency. The width is defined the same as
for the double notch filter.
The gain at the center frequency is 0 dB. Small values for width (a narrow bandpass) may
produce a very quiet signal unless the center frequency matches the frequency of a strong sine
wave partial. Wide bandpasses may result in a quiet signal if they're centered in a region of the
sound where the partials are weak. You can easily boost these quiet signals with the parameters
on the F4 AMP page.
Bandpass Filter:
Frequency
Bandpass Filter:
Width in octaves
10 100
0
C 4
-10
-20
-30
-40
Width = 2 octaves;
center frequency
-50
from C 4 to C 10
-60
-70
-80
10 100
0
-10
-20
-30
-40
-50
Center frequency = C 6
-60 width from .1 to 4 octaves
-70
-80
Frequency in Hertz
1000 10000
Frequency in Hertz
1000 10000
.1
DSP Functions
The DSP Functions
100000
C 10
100000
4
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