Sequential prophet 5 - Oscillatora

^J'^--:H&!M^-V
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2-3
OSCILLATOR
A
CSC
A is
an
audio-frequency
source
always
under
control
of
the
keyboard.
OSCILLATOR
A
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I
I
*
10
rREOUfMCV
10
PULSE
WIDTH
Figure
2-1
FREQUENCY
knob;
Controls
pitch
(oscillator
tuning).
Stepped
(quantized)
in
semitones
over a
four
-octave
range.
Exact
pitch
is
set
with
the
MASTER
TUNE
knob.
SAWTOOTH
SHAPE
switch;
When
on,
enables
a
full-level
sawtooth
wave
containing
all
harmonics.
This
unmodified
shape
is
often
described
as
"brassy."
PULSE
SHAPE
switch;
When
on,
enables
a
full-level
rectangular
wave
whose
harmonic
content
depends
on
the
setting
of the
PULSE
WIDTH
knob.
If
neither
SHAPE
switch
is
on,
OSC
A
will
have no
output to
the
mixer.
If both
SHAPE
switches
are
on,
the
sawtooth
and
pulse
are
mixed at
full
level
and
supplied
as
OSC
A's
output
to
the
mixer.
PULSE
WIDTH
knob;
Adjusts
the
harmonic
content
of
the
pulse
wave
by
setting
its
duty
cycle
from
approximately
1
to
99%. A
50%
duty-cycle
pulse
(having
only
odd
harmonics),
also
called a
square
wave,
can
be
obtained
by
setting
the
knob to
approximately
5,
then
carefully
adjusting
for the
dropout
of
the
second
harmonic
(the
first
octave
overtone).
Of
course
this
knob
is only
effective
if the
PULSE
SHAPE
switch
is on.
At
the
extreme
knob
settings
the
pulses
may
"thin
out"
until they
degenerate
to dc,
resulting
in
no
output
signal.
This
knob
has no
effect
on
the
sawtooth
wave.
SYNC
switch;
Forces
OSC
A to
follow
OSC
B in
"hard"
synchronization,
so
it
will
therefore
tune
only
to
harmonic
frequencies
of
OSC
B.
Intermediate
FREQUENCY
knob
settings
will
produce
unusual
wave
shapes
(and
therefore
unusual
timbres)
at
the
next
lower
harmonic
of OSC
B.
When
a
wide-width
pulse
is
selected
for
OSC
A
in
sync
with
OSC
B, and
OSC
B's
frequency
is
set
much
higher
than
OSC
/K, the
signal
from
OSC
A
may
degenerate
to
dc
since
the
pulse
is not
given a
chance
to
discharge
before
being
resynced.
To gain
an
understanding
of
SYNC
effects,
check
programs
l-'t, 1-7,
2-7,
3-2,
'^-2,
and
^-5
in
Program
File 1.
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CMIOOOD
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