3D Model
The SIN-COS Oscillator is a
quadrature oscillator that generates two sine
waves which are always displaced 90 degrees in
phase from one another ([SIN+] & [COS+]).
This phase difference provides exactly the
correct relationship for swirling a sound
through quadraphonic space in a circular
pattern. Since the oscillator has a basic
range from longer than 20 seconds per cycle to
500 cycles per second, many effects can be
produced. Swirling a sound at an audio rate
produces interesting spatial and modulative
effects.
In addition, the module includes two
additional outputs that are both phase shifted
a further 180 degrees ([SIN-] & [COS-]).
[SIN+] has a 0 degree phase shift, [COS+] has
a 90 degree phase shift, [SIN-] has a 180
degree phase shift and [COS-] has a 270 degree
phase shift.
Additional features include linear
VCA's for each set of outputs, so that spatial
swirls can be made to decrease in size,
effectively spiralling inward.
A [HOLD] input 'freezes" both outputs
whenever pulsed high. Thus a swirl can be
stopped at a given location, with the sound
just 'hanging there' until operation is
resumed.
Switches on the panel allow for
disabling of either the [SIN+] & [SIN-]
outputs, the [COS+] & [COS-]) outputs or
all outputs, a feature which has been found to
be useful for live performances.
What is it useful for ? Mostly it is
for modulating simultaneously up to four
sources at the same rate but out of phase.
This makes it possible to achieve so called
"Barber pole" effects or "Shepard tones". For
example, imagine that you connect each output
of the SIN-COS Oscillator to the V/oct input
of four different VCOs, then you'll hear
continuous though steady (paradoxical, ain't
it !) rising and falling intermangled pitches.
It can be used also to drive four
VC-panners to create rotating sound effects
that fill the stereo space.
