2009

Table Of Contents
BandPass: Only the frequency band directly surrounding the center frequency is
allowed to pass. All other frequencies are cut. The Resonance parameter controls the
width of the frequency band that can pass. The bandpass filter is a two-pole filter
with a slope of 6 dB/octave on each side of the band.
Notch: The frequency band directly surrounding the center frequency is cut. All other
frequencies are allowed to pass. The Resonance parameter controls the width of the
frequency band that is cut.
Cutoff knob (morphable): Determines the cutoff or center frequency, depending on the
chosen filter type. In a lowpass filter, all frequency portions above the cutoff frequency
are suppressed, or cut off, hence the name. The cutoff frequency controls the brilliance
of the signal. The higher the cutoff frequency is set, the higher the frequencies of signals
that are allowed to pass through the lowpass filter.
Resonance knob (morphable): Sets the filter resonance value.
In highpass and lowpass modes, Resonance emphasizes the portions of the signal
that surround the center frequency.
In Peak, Notch, and Bandpass modes, Resonance controls the width of the band that
surrounds the center frequency.
Key knob: Adjusts the key tracking of the cutoff frequency. Put plainly, the further up
or down the keyboard you play, the more bright or mellow the sound becomes. Put
more technically, the cutoff frequency is modulated by keyboard position. A value of
0.0 disables key tracking. A value of 1.0 makes the cutoff frequency follow the
fundamental of the note across the entire keyboard range. Play an octave higher and
the cutoff frequency also changes by an octave.
Velo Sens knob: Determines how cutoff frequency responds to incoming MIDI note
velocities. The harder you strike the keyboard, the higher the cutoff frequency—and,
generally, the brightness of the sound—becomes. A value of 0.0 disables velocity
sensitivity. A value of 1.0 results in maximum velocity sensitivity.
344 Chapter 14 Sculpture