21
MODULATION CONTROLS CONT.
PITCH AMT OSC 2 ONLY:
Pressing this button applies pitch modulation to oscillator 2 only, with no
effect on oscillator 1. The button illuminates when it’s engaged.
If you engage the
HARD SYNC OSC 2
button (which phase-locks the oscillators), then modulating
oscillator 2’s frequency with an LFO or envelope will change the oscillator’s harmonic content but not
its pitch.
FILTER AMT:
Use this knob to specify the depth of variation applied to the filter’s cutoff frequency
when the
MOD
wheel is engaged. Applying LFO modulation to the filter is useful for generating slow
filter sweeps, wobbles, and repeating effects.
WAVE AMT:
Use this knob to specify the depth of variation applied to the waveform of both
audio oscillators when the
MOD
wheel is engaged. As the waveform is modulated, the amplitudes,
frequencies, and phase of the harmonics change dynamically. Waveform modulation has no effect on
the sub oscillator, which always generates a square wave.
NOTE:
Using Shift mode or the plug-in editor, you can also assign Wave Amount to affect oscillator 1 or 2
independently (see Hidden Parameters on pg. 28).
TRY THIS
LFO WAVEFORMS
It’s likely that much of the time when you’re playing melodic sounds, you’ll use the
MOD
wheel
to control note vibrato to make your playing more expressive. To try this, begin by selecting
your favorite lead or solo preset. In the
MODULATION
section, turn the
SOURCE
knob
counterclockwise to its triangle-wave position. Turn
PITCH AMT
up to 2 and turn
LFO
RATE
to 6. Play a note and nudge the
MOD
wheel up slightly to produce vibrato. Play a few more
notes, adding vibrato during sustained notes when it feels appropriate. Adjust the
LFO RATE
to taste.
Learn your way around the LFO by trying the other waveforms and destinations, and by
varying the
LFO RATE
and depth. Begin by turning up the
PITCH AMT
knob slightly, raising
the
MOD
wheel, and then switching the
SOURCE
knob to the square wave setting. Square
wave LFO modulation produces a trill that alternates between two pitches. Varying the
LFO
RATE
changes the speed of the trill, and varying the
PITCH AMT
or the
MOD
wheel depth
changes its interval.
Now vary the
LFO RATE, PITCH AMT
, and
MOD
wheel depth using the
SOURCE
knob’s
sawtooth, ramp, and sample-and-hold settings. Notice that sawtooth and ramp-wave
modulation work best at slow rates, and sample-and-hold modulation works really well when
it’s applied to modulate the filter with
RESONANCE
turned up at least halfway. When you’re
exploring filter modulation, try turning down the oscillator signal and turning up the noise.
PULSE WAVE MODULATION
By routing LFO or envelope modulation to an oscillator’s wave amount, you give the
waveform motion by changing its harmonic content dynamically. As the control signal
changes, so does the waveform. Although the Sub Phatty’s continuously variable oscillators
let you apply modulation to any waveform, it’s most traditional to modulate a pulse wave.
Beginning with an initialized patch, turn up oscillator 1 in the
MIXER
section and turn the
WAVE
knob halfway between square and pulse. Set the
LFO RATE
at approximately 3Hz and
the LFO waveform to triangle.
