Dave Smith Instruments Sequential PROPHET X, Руководство пользователя, Страница: 108 / 172

96 Modulation Techniques Dave Smith Instruments
6. With the LFO 3 parameters shown in the main display, press Soft
Button 3 to select the
lfo dest
menu tab, then select
osc
2
shape
with
Soft Knob 1.
7. Set LFO 3
frequency
to 72 and LFO 3
amount
to 68. Note that these
settings differ from those set for LFO 2/oscillator 2
8. Play some chords. Basic PMW string sound!
To hear what a difference pulse-width modulation makes, remove it by
turning the LFO
amount
parameter for both LFO 2 and LFO 3 to zero.
You can use this technique to add harmonic movement to any of the
oscillator waveshapes, not just the pulse wave. But be aware that if you
set the amount of waveshape modulation too high on the pulse wave, it
will become so narrow that the wave’s sound will disappear!
Modulating the Stereo Filters Independently
Because the Prophet X has stereo filters (in 8-voice mode), you can add
even more movement by using the LFOs (or other sources) to indepen-
dently modulate the left-channel and right-channel filter cutoff. This
produces some interesting stereo filtering effects. We’ll re-use the same
two LFOs in the example below. The mod matrix makes it possible to
route the same source to multiple destinations.
To modulate the left and right channels of the stereo filters:
1. Start with the PWM string sound from the previous example.
2. In the
modulation
section, press the
assign source
button. Use s
oft
k
nob
1 to scroll to the first available mod slot.
3. Use s
oft
k
nob
2 to scroll through the various mod sources and choose
lfo
2.
4. Use s
oft
k
nob
3 to set the amount to 20.
5. Use s
oft
k
nob
4 to scroll through the various mod destinations and
choose
cutoff
l.
6. Now do the same for LFO 3 and the right filter channel: Use s
oft
k
nob
1 to scroll to the next available mod slot.