Sequential Split-Eight - LFO Parameter Details

TRIANGLE WAVE
Value Range: 00/01
00s Off
01= On
Enables full-level triangle wave, containing little harmonic energy,
thus having a dull tone.
PULSE WAVE
Value Range: 00/01
00s Off
01= On
Enables full-level waveshape whose harmonic content, thus timbre,
depends on the value of PULSE WIDTH and LFO modulation. If
switching this on produces no sound, try adjusting Pulse Width to a
value between 2 and 60.
Note: If all three waveshapes are on, and the filter is well open, some
distortion may occur when several keys are played simultaneously. If
this occurs, compensate by simply reducing VOICE VOLUME.
PULSE WIDTH
Value Range: 00-63
0U 1%
15= 25%
31= square wave
47= 75%
63= 99%
Adjusts the harmonic content of the pulse wave by varying its duty
cycle from approximately 1 to 99%. At the extreme parameter values
(00-02 and 60-63) the pulses may be barely audible. A 50% duty-cycle
pulse (having only odd harmonics), also called a square wave, can be
selected (approximately value 31).
This parameter is only effective if PULSE is on. This parameter has
no effect on the sawtooth or triangle waves.
POLY-MOD
Value Range: 00-15
In Double Mode, the Output of Channel B is applied to the external
signal input of the Channel A filters. Channel A oscillator output is
switched to externally-modulate these filters, Thus, Channel A
modulates Channel B. Channel B and the Channel A VCO output is
disabled. Of course, there is a four-voice limit.
Note that if value range is set very low, this will activate the patch
switching arrangement (disabling Channel B), but provide little
effect.
CM608A
13
LFO
"Modulation" refers to a periodic or consistent (as opposed to
accidental) aural change which is interesting or musically useful.
Modulation is created by electronic controllers when it is not possible
to adjust a mechanical controller with the required speed or
precision. Modulation systems thus free the hands for playing the
keyboard.
Modulation involves a signal-generating source and a modulated
destination. LFO-MOD has a low-frequency oscillator (LFO) as a
source, but has three selectable destinations. The LFO frequency,
waveshape, and basic output level are adjusted by three parameters.
To this modulation level will be added any contribution of the MOD-
wheel. Total modulation is applied by the LFO switches to three
destinations.
FREQUENCY
Value Range: 00-15
Adjusts LFO frequency from about K to 20 Hz.
PROGRAMMED AMOUNT
Value Range: 00-31
Programs modulation depth independently from the MOD wheel.
TRIANGLE/SQUARE WAVE SHAPE
Value Range: 00/01
00=T dangle
OUSquare
Selects a triangle wave for vibrato, or a square wave for trills.
OSCILLATOR MODULATION
Value Range: 00/01
00= Off
01= On
This enables LFO modulation to the oscillator frequency, according
to the level set by LFO AMOUNT and the MOD wheel. This produces
a vibrato or trill, according to the value of LFO SHAPE.
PULSE-WIDTH LFO-MODULATION
Value Range: 00/01
00= Off
01= On
Applies LFO-modulation to oscillator pulse width.
CM608A