Kurzweil PC3K6, Musician'S Manual

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9-18
Effects
Filters
Spacing determines the starting pitch of the descending buzz and how fast it descends, by
setting the initial separation of impulses and the subsequent rate of increasing impulse
separation. The spacing between impulses is given in samples (20.8 μ s). At low values, the buzz
starts at high frequencies and drops slowly, while at high values the buzz starts at a lower pitch
and drops rapidly. Range is 0.0 to 40.0 samples, with a resolution of 0.2 sample.
Contour controls the overall shape of the reverb. When set to a high value, sounds passed
through the reverb start at a high level, and it slowly decays. As the control value is reduced, it
takes more time for the effect to build up before decaying. At a value of around 34%, the reverb
behaves like a reverse reverb, building up to a hit. When it is set to zero, the algorithm acts like a
simple delay. Range is 0 to 100%.
Filters
There are four types of Resonant Filter algorithms in the PC3K. All of them have these
parameters in common:
Filter Type (or FiltType ) can be Lowpass, Highpass, Bandpass, or Notch (band ‐ cut).
Resonance is the resonance of the filter, adjustable from 0 to 50 dB.
Resonant Filter
Frequency (or Freq ) is the fixed resonant frequency of the filter. Its range is 16 to 8372 Hz.
Envelope Filter
Envelope Filter is a resonant filter whose center frequency can be made to vary according to the
level of the incoming signal.
Filter Type can be Lowpass, Highpass, Bandpass, or Notch (band ‐ cut).
Min Freq is the minimum resonant frequency of the filter, that is, the filter frequency when the
input gain is below the triggering threshold. Its range is 16 to 8372 Hz.
Sweep determines how far the resonant frequency moves when the input level increases. At
positive levels it moves up in pitch, and at negative levels it moves down. The highest possible
resonant frequency is 8372 Hz, the lowest is 0 Hz. This parameter’s range is ‐ 100% to +100%.
Resonance is the resonance of the filter, adjustable from 0 to 50 dB.
Atk Rate adjusts the upward slew of the attack portion of the envelope detector. Range is 0 to
300.0 dB/sec.
Rel Rate adjusts the downward slew of the release portion. Range is 0 to 300.0 dB/sec.
Smooth Rate slows down the envelope follower. If it is set to a lower rate than Atk Rate or Rel
Rate , it can dominate those parameters. Range is 0 to 300.0 dB/sec.
Triggered Filter
The Triggered Filter is a sweeping resonant filter that triggers when a certain input threshold is
reached, and then follows its own envelope, consisting of an instantaneous attack and an
exponential release, rather than the envelope of the input signal.
Max Freq is the resonant frequency of the filter at the peak of the internal envelope. It can be set
lower than Min Freq (above), in which case the filter will sweep downwards, then back up.
Range is 16 to 8372 Hz.