FXAlg #902: LFO Sweep Filter
Algorithm Reference-121
PAGE 2
Wet/Dry
The amount of modulated (wet) signal relative to unaffected (dry) signal as a percent.
Out Gain
The overall gain or amplitude at the output of the effect.
LFO Tempo
Basis for the rates of the LFO, as referenced to a musical tempo in bpm (beats per
minute). When this parameter is set to ÒSystemÓ, the tempo is locked to the internal
sequencer tempo or to incoming MIDI clocks. When it is set to ÒSystemÓ, sources (FUNs,
LFOs, ASRs etc.) will have no effect on the Tempo parameter.
LFO Period
Sets the LFO rate based on the Tempo determined above: the number of beats
corresponding to one period of the LFO cycle. For example, if the LFO Period is set to
Ò4Ó, the LFOs will take four beats to pass through one oscillation, so the LFO rate will be
1/4th of the Tempo setting. If it is set to Ò6/24Ó (=1/4), the LFO will oscillate four times
as fast as the Tempo. At Ò0Ó, the LFOs stop oscillating and their phase is undetermined
(wherever they stopped).
LFO Shape
The waveform type for the LFO. Choices are Sine, Saw+, Saw-, Pulse, and Tri.
LFO PlsWid
When the LFO Shape is set to Pulse, the PlsWid parameter sets the pulse width as a
percentage of the waveform period. The pulse is a square wave when the width is set to
50%. This parameter is active only when the Pulse waveform is selected.
LFO Smooth
Smooths the Saw+, Saw-, and Pulse waveforms. For the sawtooth waves, smoothing
makes the waveform more like a triangle wave. For the Pulse wave, smoothing makes
the waveform more like a sine wave.
FilterType
The type of resonant Þlter to be used. May be one of ÒLowpassÓ, ÒHighpassÓ,
ÒBandpassÓ, or ÒNotchÓ.
Min Freq
The minimum frequency of the resonant Þlter. This is the resonant frequency at one of
the extremes of the LFO sweep. The resonant Þlter frequency will sweep between the
Min Freq and Max Freq.
Max Freq
The maximum frequency of the resonant Þlter. This is resonant frequency at the other
extreme of the LFO sweep. The resonant Þlter frequency will sweep between the Min
Freq and Max Freq.
Resonance
The resonance level of the resonant Þlter. Resonance sets the level of the resonant peak.
In the notch Þlter, this sets the amount of cut, so 0 dB provides the highest, widest notch,
and higher levels make the notch increasingly narrower and shallower.
L Phase
The phase angle of the left channel LFO relative to the system tempo clock and the right
channel phase.
R Phase
The phase angle of the right channel LFO relative to the system tempo clock and the left
channel phase.
FilterType
Lowpass
Min Freq
16 to 8372 Hz
Max Freq
16 to 8372 Hz
Resonance
0 to 50 dB
L Phase
0.0 to 360.0 deg
R Phase
0.0 to 360.0 deg
L
R
0Hz 2k 4k 6k
0Hz 2k 4k 6k
