Kurzweil K2600 - Page 504

16-20
DSP Functions
The DSP Functions
The two-pole notch Þlter has two control-input pages, one for center frequency, one for width.
Partials with frequencies above or below the notch will be unaffected. Within the notch, partials
will be attenuated according to the width of the notch. The width is deÞned in terms of the
number of octaves between the points on the signalÕs attenuation curve where the attenuation is
3 dB (see the explanation of F2 WID for the PARAMETRIC EQ functionÑpage 16-26). For
example, if the width is set at four octaves, then the attenuation will be 3 dB at two octaves in
either direction from the center frequency. ThereÕs no attenuation of partials at more than two
octaves in either direction from the center frequency.
Two-pole Notch Filter, Fixed Width (NOTCH2)
The only functional difference between NOTCH2 and NOTCH FILTER is that the width of
NOTCH2 is Þxed at 2.2 octaves. This gives you a one-stage notch Þlter function.
-80
-70
-60
-50
-40
-30
-20
-10
0
10 100 1000 10000 100000
Frequency in Hertz
Amplitude in dB
Center frequency
width from .1 to 4 octaves
= C 6;
4
.1
2-Pole Notch Filter:
Width in octaves
-70
-60
-50
-40
-30
-20
-10
0
10 100 1000 10000 100000
Frequency in Hertz
Amplitude in dB
Center frequency
at C 4, C 7, C 10
C 4
C 10