The Pigtronix Active Dual CV Expression pedal allows you to control modular synths and outboard gear that requires 0-5V control voltage (CV) signals to modulate parameters such as filter cutoff, LFO speed, resonance and more. With two independent active 0-5V CV outputs this unqiue device can control multiple parameters simultaneously and will allow polarity reversal of one side when desired.
The Dual CV Expression pedal is an exclusive product developed by David Koltai for the synth heads at Nova Musik.
It’s worth pointing out here that this pedal started life as another Pigtronix product simply called the Dual Expression Pedal, which is a passive pedal designed to work with the TRS expression inputs found on many guitar effects pedals. We’ve modified the existing passive Dual Expression Pedal to add a 18VDC power input designed to provide with 0-5V control voltages so that it could be used with eurorack standard CV connections.
The Pigtronix Dual CV pedal is designed for use with mono/TS cables with a 1/4” TS connection at the pedal end and either a 1/8” (eurorack) or 1/4″ (Moog-style) TS connection at the other.
Make sure you are using the 18VDC 300mA 2.1mm center-negative power supply that came with your Pigtronix Custom Shop Active Dual CV Expression Pedal. Plug the power cord into the jack on the side of the pedal and then plug the power adapter into an electrical socket.
The pedal is now powered up. To turn the device off, unplug it from the wall or turn off the power going to the socket that the power supply is plugged into.
The Pigtronix Custom Shop Active Dual CV Expression Pedal uses two 1/4″ TS phone plug outputs on the underside of the pedal. Connect the outputs to control voltage inputs on your device(s) using either 1/4″ TS to 1/4″ TS or 1/4″ TS to 1/8” TS instrument cables. If you only intend to use the pedal with one device/input, you can connect either output and leave the other unused.
TS stands for Tip, Sleeve and is a two-conductor cable. It is sometimes also called a mono or unbalanced cable or a patch cable. The pedal is designed to be used with cables that have TS connectors at both ends.
Figure 1. A TS connector with the two conductors separated by the black insulation band. The pointed front of the connector is the tip and the large conductor at the rear nearest the plug body is the sleeve.
The voltage range of the Custom Shop Active Dual CV Expression Pedal is 0-5V. Some devices will require proper configuration, and depending on the input/parameter you’re controlling it may be desirable to use an attenuator between the pedal and the control voltage input, such as the Moog CP-251 Control Processor or any number of eurorack mixer/attenuator modules. Used without an attenuator, the audible effect that the pedal has on your input may vary widely.
Be sure to read the user manual for your device, and set up and calibrate the expression pedal in accordance with the instruction if necessary. Most manufacturers have copies of their user manuals available online.
Moving the rocker on the expression pedal will change the output voltage between minimum (0V) at heel down and maximum (5V) at toe down. If used, both outputs will vary simultaneously.
The direction of OUT1 can be reversed using the small toggle switch at the front of the pedal. The factory default is normal operation with the toggle switched towards the rear of the pedal. To reverse the direction of OUT1, switch the toggle towards the front of the pedal. The sweep on OUT1 will now be reversed, with maximum at heel down and minimum at toe down. OUT2 cannot be reversed.
The tension of the rocker can be adjusted using the tension adjustment screw on the rear of the pedal between the rocker and the base. Use the hex key provided to tighten the adjustment screw until the pedal remains in place. It may be necessary to adjust this screw every once in a while to compensate for use and environmental conditions such as very hot or cold weather when the pedal has been stored for a long period or after shipping. Replacement hex keys are available from Mission Engineering.