Crumar Spirit - Control System; Modulation and Envelope Controls

CONTROL
MASTER
OSCILLATOR A
OSCILLATOR B
TUNE
OCTAVE WAVEFORM
SYNC. WAVEFORM
OCTAVE / RANGE
TRIGGER
INTERVAL
SINGLE
GATE SELECT
KBD x
ON
v / eXT
ON
MOO : ?< . · . SHAPER Y
.0.
·0·
A. "-
. .
O
0
.
20 '"
. . . .
A ......... - '1 WIDE _4 _4
. . ..
o
o
000
C:
0
•• _ 31
UNISON • • BASS
20 1 ~
rt..
MASTER VOLUME MASTER
KB AMOUNT
0--; 0 oQ.
L _ _ , I L _ _ ,
-CUTOFF -I- RESONANCE :- SLOPE -- TRACKING I -
I I
I , _ __ .J
BRIGHTNESS A B RING NO I SE
A
B NOISE
"o J 20B
.0.
OUT ~~~S
O V ER - BANO -
LO\NER ONLY DRI V E PASS.
SHAPER V PATH - FIL TER/ADSR PATH - LOWER FILTER L
The Spirit has a variety of control resources. Chief among these are two dedi·
cated ADSR envelope generators, and two sources of modulation: MOD X,
and SHAPER Y.
MOD X is the primary source of modulations on the Spirit. All periodic/clo-
cked modulations from MOD X are controlled in rate by a low frequency
oscillator (LFO), which is also the sample-and-hold clock. The ARPEGGIA-
TOR section creates repeating pitch patterns according to which keys are
depressed
on the digitally-scanned keyboard and which arpeggiation mode is
selected. I n addition, slow-moving random (red noise) and Oscillator Bare
among the MOD SOURCE selections.
SHAPER Y is used primarily to create "one-shots ," or envelopes with a sim-
ple shape. I n the FREE MODE it becomes a secondary LFO, a source of low
frequency variable symmetry waveforms.
Each selected MOD X and SHAPER Y signal is routed through its respective
wheel
on the performance panel; each wheel is an attenuator that lets you
control signal size. X and Y attenuated signals are routed to various destina-
tions by respective rotary switches in the WHEEL DESTINATIONS section .
I n addition, the SHAPE X WITH Y switch allows "second order" modula-
tion; in this case the SHAPER Y section shapes the size of the MOD X signal.
This allows automatic shaping of vibrato depth, for instance.
The FI L TER ENVELOPE is permanently connected to the cutoff frequency
control input of the UPPER FI L TER U. I t is connected to the LOWER FI L-
TER L only when the TRACKI NG switch is in the DYNAM IC position . The
signal from the FI L TER ENVELOPE is attenuated (controlled in size) by
the AMOUNT control. The NORMAL side of AMOUNT provides a "positi-
ve" envelope that rises and falls; the INVERT side pro vides an inverted, or
mirror-image version that falls and rises. I n either case the envelope straddles
the cutoff frequency set by the CUTOFF control. An unattenuated envelope
moves the cutoff frequency from 2.5 octaves below to 2.5 octaves above its
cutoff setting.
The LOUDNESS ENVELOPE is permanently connected to the VCA in the
FI L TER/AOSR audio signal path. When VCA BYPASS is on, the VCA is
biased fully open; that is, LOUDNESS ENVELOPE ADSR settings have no
effect in BYPASS mode and sounds will not be articulated, but uninter-
rupted .
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