4
Q U I C K S T A R T
Modulation source:
The simplest use of an LFO is often the best: apply continually changing
modulation to some parameter, such as a pitch input (for vibrato), a filter cuto
ff
, or (with an o
ff
set)
to a VCA control.
Clock/trigger:
To use one of the LFOs as a periodic trigger, a voltage controlled clock, or some
other digital signal, use the appropriate jumper to set a pulse wave output.
Rhythmic LFO:
With the expander attached, plug all four phase related outputs into an analog
logic ANY (maximum), such as Babel. Adjust the phase of each LFO, so that the LFO varies with a
particular rhythm.
Clock synced LFOs:
When you select a pulse wave output, this does not a
ff
ect the output of the
LFO Phase Expander. This means that a pulse wave output with an attached expander will give
you three phases of LFOs synced to a clock signal. Pair this with a clock divider or multiplier to get
all kinds of rhythmic options.
Quadrature LFO:
When all three knobs of the phase expander are centered, the four related
LFO signals will be in quadrature with each other. Quadrature has many uses, such as rotating a
signal between four speakers.
M O D E L A N D P A R A M E T E R S
The Quad LFO provides four sinusoidal outputs with a linear rate control, according to the follow-
ing equation:
Or alternately, a pulse wave output according to the following piecewise equation:
is proportional to
FM
and
FREQ
via the following relation:
Where the
FREQ
knob ranges from zero to 5 volts, at zero is approximately zero,
and at 5 volts is approximately 23 Hz.
The phase expander produces three more sine wave outputs according to the following equations:
Where ranges from 0° to 180°, ranges from 90° to 270°, and
ranges from 180° to 360°.
y= sin(ωt)
y=
{5
−5
sin(ωt) ≥ 0
sin(ωt) < 0
ω
ω∝F M +F REQ
F M +F REQ
F M +F REQ
y =
1sin(ωt −ϕ
)
1
y =
2sin(ωt −ϕ
)
2
y =
3sin(ωt −ϕ
)
3
ϕ =
1P HASE
1ϕ =
2P HASE
2
ϕ =
3P HASE
3
