Dave Smith Instruments PROPHET 12 DESKTOP - Manual (Page 25)

13 Prophet 12 Module Operation Manual Oscillators
S
HaPe
m
od
/P
ulSe
W
idtH
affects the pulse width or duty cycle of the Pulse wave.
0
Pulse Width
-64 63
When Triangle is the selected shape, the width of the wave is changed, similar
to Pulse and Sawtooth, adding harmonics and getting more thin sounding when
turned in either direction from 0.
With Sine as the selected shape, values less than 0 gradually add another sine an
octave higher than the base pitch. Values greater than 0 cause the sine wave to
gradually be clipped, adding harmonics and sounding somewhat distorted.
For the 12 wavetable shapes, S
HaPe
m
od
/P
ulSe
W
idtH
crossfades between the
selected shape and the Wave Left and Wave Right selections. Let’s say, for
example, that the selected wave shape is Mellow, Wave Left is set to Tines, and
Wave Right is set to Nasal. A S
HaPe
m
od
/P
ulSe
W
idtH
setting of -64 will be the
Tines wave, 0 will be Mellow, and +63 will be Nasal. Values between -64 and
0 will be a mix of Tines and Mellow; values between 0 and +63 will be a mix
of Mellow and Nasal. An extremely broad variety of hybrid wave shapes can be
created by mixing two of the wavetable shapes. And, of course, S
HaPe
m
od
/P
ulSe
W
idtH
is a modulation destination, so an LFO or other modulation source can be
routed to it. Note that the algorithm used to mix the waves is not simply a mix. If
all three are set to the same wave, there will still be a noticeable difference in the
sound as Shape Mod changes.
S
HaPe
m
od
/P
ulSe
W
idtH
also works when noise is the selected shape. With a
Shape Mod value of 0, the displayed noise type is what is heard. Values less than
0 gradually cause it to change to a second noise type. Values greater than 64
cause it to change to a third noise type. The left and right noise sources are fixed.
Try it. It’s much easier to hear than to explain! The display also provides a visual
indication of the change.
Wave Left, Wave Right— Sets the wavetable shapes used in conjunction with
the S
HaPe
m
od
/P
ulSe
W
idtH
parameter. Wave Left and Wave Right are only
active when one of the twelve wavetables is selected as the primary oscillator
shape. See “Shape Mod/Pulse Width” for more information.