The Voice Controller module for Rack implements the auto-calibration part of the VST version, allowing you to automatically calibrate and tune your VCOs and interfacing hardware.

Calibration Input: connect to the audio output of your VCO (typically via Rack's Audio module). The module only uses this input during calibration.

Pitch CV Input: connect the pitch CV that you want to use to drive the VCO (e.g. the output of a sequencer).

Pitch CV Output: connect to the pitch CV input of the VCO.

To run the calibration:

• Ensure the Calibration Input and Pitch CV Output are connected.
• Enable the Hz/V button if the VCO has a Hz/V response. If in doubt, leave this off.
• Press the Start calibration button.

The calibration result is part of the module's Preset, and so can be saved and loaded in the usual way (via Rack's contextual menu).

The AC Encoder is a straight copy of the VST version, and enables use of non-DC-coupled audio interfaces for outputting CVs. Please review the AC Encoder page.

It can be used particularly conveniently with the ES-1 Emulation algorithm of the Expert Sleepers disting module.

The In socket is where you connect the CV that you want to output to the hardware.

The Out socket should be connected to your audio interface (e.g. via Rack's Audio module).

The Bipolar/Unipolar switch should be set appropriately for the input CV (e.g. bipolar for LFOs and unipolar for envelopes).

The Min Out and Max Out knobs set the minimum and maximum voltages that the plug-in will output. In an ideal world these would be left at 0.0 and 10.0 respectively to maximise the possible range of voltages. However sometimes this is not the best solution in practice. For example, the simple rectifier circuit as described on the website usually suffers from a 'dead zone' at low voltages. In this case, you would want to raise the Min Out setting so that the plug-in would only output voltages above the dead zone. Similarly, some systems exhibit nonlinearities at higher voltages, in which case you would bring down the Max Out setting to avoid these effects.

The CV Input module is a copy of the VST version in 'ES-2 Decoder' mode. It allows you to bring CVs from a hardware modular into Rack via an audio interface.

It can be used with the Expert Sleepers ES-2-2 module, or the Expert Sleepers disting module's ES-2 Emulation algorithm.

The In socket should be connected to the output of the (emulated) ES-2, via the audio interface and Rack's Audio module.

The Out socket outputs the recovered CV.

The Offset knob should be adjusted so that a zero Volt CV input to the ES-2 results in a zero output from the CV Input module.

The Scale knob applies a simple multiplier to the output.

The Smooth knob applies smoothing to the output, which can help remove any residual noise.

The CV To MIDI module has no direct counterpart in the VST version, but is related to some functionality in the ES-4 Controller/ES-5 Controller VST plug-ins. It allows you to output MIDI from Rack via an Expert Sleepers ES-5, ESX-8GT, or ESX-8MD module. As such, it can generate sample accurate MIDI for jitter-free sync and sequencing.

This module requires our other VCV Rack plug-in, the free Encoders, to route its output to the ES-5 or ES-4(0).

Run: causes the module to output a MIDI start message when the input signal goes over 1V, and a MIDI stop message when the input signal goes below 0.5V.

Clock: causes the module to output a MIDI clock message on every rising edge.

CV/Gate/Vel: a MIDI note on message is output when the Gate goes high, and a note off when the Gate goes low. The CV input is sampled at note on and used to determine the pitch of the MIDI note. Likewise, the Vel input is sampled for the note velocity. The range 0-10V corresponds to MIDI velocities 1-127. If the Vel input is unconnected, a velocity of 127 is used.

These three inputs (only) support polyphonic cables.

Aftertouch: MIDI aftertouch (aka channel pressure) messages are generated when this input changes. The range 0-10V corresponds to MIDI values of 0-127.

Bend: MIDI pitch bend messages are generated when this input changes. The range ±5V corresponds to MIDI values of -8192 to 8191.

The Out socket should be connected to an 8GT Encoder.

This module has a contextual menu (right click) for choosing the output MIDI channel.