Future Retro XS - Manual (Page 16)

CONTROLLING YOUR XS
USING CV/GATE CONTROL SIGNALS
External control voltage and logic gate signals can be used at any time in any combination to control the
XS, even while MIDI note data is being received. Receiving MIDI data is the default way to play the
XS. But when an analog voltage or gate signal is inserted into one of the control inputs it can either be
selected to modulate a specific parameter, or in some cases will automatically override the control signal
being generated by the internal MIDI to CV/Gate converter.
The CV IN input is routed to the CV Track control in the PITCH CONTROL section. This control
determines which source Oscillator A and B will use to control their pitch.
In the A B position, both oscillators will be controlled by MIDI notes received.
In the A BX position, Oscillator A will respond to MIDI notes received, while
Oscillator B will be controlled by an external voltage inserted into the CV IN
jack.
In the AX B position, Oscillator A will be controlled by an external voltage
inserted into the CV IN jack, while Oscillator B will be controlled by MIDI notes
received.
In the ABX position, both oscillators will be controlled by an external voltage
inserted into the CV IN jack.
Note: If no signal is inserted into the CV IN jack, and one or both of the oscillators are selected to use
the external voltage, these oscillators will produce a stationary pitch, which can be useful for certain
effects.
The GATE IN input is used to trigger the internal envelope circuits. Any time a cable is inserted
into this jack, it will override MIDI triggering of the envelopes. Typically, you will want to use any
logic gate signal ranging from 0 to +15 volts. Any voltage received higher than +1.5 volts will be con-
sidered as a Gate On, and any voltage less will be considered as a Gate Off. This input can also accept
negative voltages without harming the unit, but if they do not exceed the +1.5 volt trip level, no gate will
be produced.
TIP: With a trip point of +1.5 volts, you can also use audio signals to trigger the envelopes in the XS.
The VEL IN input is used to control the amplitude of both envelopes (depending on the velocity
amount setting used for each), and can also be used to directly modify the pitch of Oscillator B and
the pulse width duration of its square/pulse wave. Any time a cable is inserted into this jack, it will
override the MIDI Velocity control voltages being generated to control these parameters. Typically, you
will want to use any control voltage ranging from 0 to +10 volts as the VEL IN source, although input
voltages can range from –15 to +15 volts without harming the unit.
TIP: Using Velocity control signals that swing both positive and negative can have interesting results.
For instance, if the Velocity input goes negative and is controlling Envelope 1’s amplitude, it will cause
the output of this envelope to become inverted. However, negative control voltages applied to Envelope
2 (the amplifier) will not allow the amplifier to pass audio to the output during the negative period. If
you do not desire this effect on the amplifier, simply turn down the Velocity control for the amplifier.
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