8-Step Envelopes - Casio CZ-3000 Operation Manual

The
revolutionary
PD
sound
source system
thus
makes
it
possible
to
output waveforms
that
differ
from
cosine
waves by simply
distorting
the cosine
(or sine)
wave
read
from
ROM,
Figs.
"I
through 3
illustrate
the patterns produced by
increasing the phase angle
read
speed
from through
it
while
decreasing the speed from
it
through
2x. This
is
the pattern
effect-
ed
when
the
SAWTOOTH
waveform
is
selected
in
the
DCO
parameter.
Read phase
angles
are also distorted
in
accordance
with the selection of the other
DCO
parameter
WAVE
FORMs,
thus
making
a variety of
waveform
outputs
possible.
The
magnitude
of
the read phase
angle
distortion corresponds
to
the
momentary
value
(change over time)
of the
DCW
envelope.
When
the
DCW
envelope
is
set
as
shown
in
Fig.
4,
an undistorted cosine wave
is
output
at
point
(a),
distortion
reaches
its
peak
at
point
©,
and
a
sawtooth
pattern as
shown
in Fig.
3
is
output. Distortion
is
reduced (modulation
become
shallower)
at
point®, and
a
pattern that
is
somewhere
between
a cosine
wave
and
a saw-tooth wave
as
illustrated
in Fig.
2
is
output.
When WAVE FORM
is
set to saw-tooth.
DCW
envelope
tey
ON
Key
OFF
POINTS TO
REMEMBER
1
)The
pattern of the read phase angle
distortion
corresponds
to the
WAVE FORM
setting of the
DCO
parameter.
2
)The magnitude
of
the read output phase
angle
distortion
(modulation depth)
cor-
responds
to
the
momentary
value of the
DCW
envelope.
8-STEP
ENVELOPES
The
CZ-3000
features a dual system
DCO/DCW/DCA,
and each system has
its
own
indepen-
dent envelope generator
for
control of changes
in notes,
timbres
and volume
over
time.
The
envelope generators can
set
up
to eight steps
including setting of the sustain point
(the
level
at
which
a
note
is
sustained while a key
is
depressed). This provides
greater
ver-
satility
than the conventional
ADSR
generator
and makes
sound
creation
possibilities
vir*
tually unlimited.
(Fig. 1)
K«y
QN
-...,'
'-!l
I
r
lV^
**£l ^\
l
i
1
*Ri
through
Rb indicate
the
RATE
(slope) of
each
various
steps,
while
Li
through
L*
in*
dicate the
LEVEL
(des-
tination
level). Lj
is
reached
at
a slope of
Rj in
STEP
l
p
L
2
is
reached
at a
slope of
R
2
in
STEP
2, etc.
C
14
8-STEP
ENVELOPES
i