Roland SH-1 - Page 29

synthesizing
sounds
6.
THE
OSCILLATING
VCF
Examples of Using
the Oscillating VCF
1. The Oscillating
VCF
Raising the VCF RESONANCE control
to
MAX causes the VCF to oscillate
by
itself.
The
frequency
of these oscillations will
depend on the
VCF CUTOFF
FREQ.
The
VCF
is calibrated for 1 volt/octave
which means that if the VCF
KYBD
control is raised to
"10",
melodies can be
played using the keyboard.
The oscillating VCF produces a
perfect
sine wave. With the settings
shown on the
right, melodies
can be played on the
keyboard,
and the
VCF CUTOFF
FREQ
control acts as
a
tuning control. Also, try
moving the ENV-2 "A" control
a
little.
2.
Whistling
The sound of whistling
is
very near the
sound of
a sine wave;
adding
a little noise
using the
AUDIO
MIXER
produces the
effect
of air
passing between the lips. To
add
a
vibrato effect, the VCF MOD control
is raised a little. Set the
MODULATOR
section
at
*\/
with
a RATE
of about
"4.5"
and
a
DELAY
TIME of
about
"3".
The
use
of ENV-1
to
control
the
VCF
produces
the
effect of an
autobend.
3. Producing
a
Sine
Wave
The
settings on the right
produce
a sound
a
little
like a
celesta.
The
VCF CUTOFF
FREQ
control acts
as
a tuning control.
Notice the differences
in the sound for
different settings of the CUTOFF FREQ
control.
A xylophone-tike sound can be produced
by lowering both "D" and
"R" of
ENV-1
to
about
"2".
Envelope
control of the
oscillating VCF
can beusedforsynthesizing
animal sounds, natural sounds, and sound
effects
(see
pp.
41
-44).
4. Pitched Noise
Try
adding noise
to
the settings
shown in
(3)
above. This
is done in the same way as
(2)
whistling
above by setting the
VCF
RESONANCE
control just below the point
where
the
VCF
starts
to
oscillate, or
at
about
"7.5".
Try various
settings
of
EN V- 1
.
You can
make the sound of maracas
this way
(see
p.
36).
"1
—
i"
^_
HI
E
=
IFO —
i.
_ _ CNVI
AH
AUDIO MIXER sliders
at
"0'
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