What is a CV?
CV stands for Control Voltage. In analog electronic musical instruments, it is a type of low-current electrical signal
used to continuously modulate a musical parameter. In the Etherwave theremin, the simplest example of a CV is the
control of the instrument’s volume by the Volume Antenna. The Volume Antenna circuitry generates a CV that in-
creases as the left hand is pulled away from the antenna. This CV is applied to the control input of a Voltage Controlled
Amplifier (VCA). As the voltage generated by the Volume Antenna circuitry increases, the output level of the VCA
increases too. We hear this as an increase in volume. For more on the subject, you may wish to refer to the “Basics of
Analog Synthesis” chapter of the Minimoog Voyager User’s Manual, or the “Basic Theory” section of the CP-251 Con-
trol Processor User’s Manual, both available on our website: www.moogmusic.com.
What is a Gate?
A Gate is a signal that has only two levels: Low and High, or sometimes called Off and On. This can be used as a trig-
ger for events, or as a switch type signal. In analog synthesizers, a gate is usually used to start or stop the sound of the
instrument by starting and stopping circuits called Envelope Generators. For example, a gate on signal is produced when
a key is pressed on the Minimoog Voyager, thus starting a note.
Using the Etherwave Plus CV Outputs.
The Etherwave Plus CV outputs are located on the bottom of the unit as indicated by the front panel, requiring the
placement of the Etherwave Plus on a mic stand to provide access.
CAUTION: Be sure you understand the
operating levels of the equipment involved before making connections.
Most modern analog equip-
ment has protection built into the inputs of a circuit to prevent damage from unexpected voltage levels. However some
equipment may respond in unexpected ways, or may not respond at all to CVs outside the expected levels.
Note that most modern Moog equipment such as moogerfooger analog effects typically specify 0V to +5V or -5V
to +5V levels for CV inputs. The Etherwave Plus will work safely with these devices despite outputting voltages greater
than specified. In general it is safe to make connections with the equipment powered up.
One thing to avoid when making CV connections is to avoid passively mixing CV output signals into a single CV
input, for instance with a “Y” type splitter cable. This can sum the voltages involved and rapidly exceed the voltage levels
expected at a CV input. This may cause unwanted results. For combining CV signals, use a CV mixer, such as the 4-input
mixer of the moogerfooger CP-251 Control Processor.
Example Applications
Connecting the Etherwave Plus to a Little Phatty analog synthesizer.
In this example we will control the Little Phatty so that it can be played in a gestural manner similar to a theremin.
• First, connect the Etherwave Plus Gate Output to the Little Phatty(LP) Gate Input.
• Second, connect the Pitch CV Output to the LP Pitch control input.
• Next, Connect the Volume CV Output to the LP Volume Control Input.
• On the LP, select a preset that is voiced in the 16’ range and has a sustaining type envelope.
Now – with your left hand away from the Volume Antenna, Move your right hand closer to the Pitch Antenna – note
the LP pitch rises. Now move your left hand close to the Volume Antenna – you will hear the LP go silent – as you lift
your left hand away from the Volume Antenna you will hear the LP start a note again.
It is really fun to try different presets out to hear the ways the Little Phatty will respond to the gestural control of the
Etherwave Plus!
