This is my collection of modules for VCV Rack:

• Transport
• Latch
• Pulse
• Range
• Negative Harmony

These modules are freely available in the VCV Rack Library.

This software is fully licensed under the GNU General Public License v3.0+, in the spirit of freely sharing with the VCV Rack and Cardinal community. At your discretion, you may alternatively use this software under the terms of the MIT license.

The panel artwork incorporates the public domain Camels Caravan Silhouette (CC0-1.0). If you publish your own fork, please use different artwork to help differentiate the models.

Typeface fonts included are licensed under the SIL OPEN FONT LICENSE Version 1.1:

• Fantasque Copyright (c) 2013-2017, Jany Belluz ([email protected])
• DSEG Copyright (c) 2017, keshikan (http://www.keshikan.net)
• Manrope Copyright https://manropefont.com/

• CHANGELOG.txt.
• VCV Rack Library updates.

You can watch this 20 minute video introduction to Transport and Latch, or you can read everything below and then download the pre-made patches:

Transport is a DAW-style play/stop/record control, with clocked punch-in/punch-out (Quantize Arming), allowing you to play and/or record anything for an exact number of clock cycles (bars). Transport can control an external recording device to create perfect loops (eg. with Lilac Looper).

Transport works both in standalone VCV Rack, or as a VST (VCV Rack Pro / Cardinal). Transport can be controlled with your host DAW transport buttons (play/stop) or other external MIDI transport via MIDI-CV, or you can use the on-device trigger buttons for PLAY, ARM, and RESET.

• Set LENGTH to the number of clock cycles (eg. beats, bars) that you wish to record. (Or toggle the button next to it OFF, to disable it, and to record an unlimited length.)
• Input a clock signal (CLK) to count the number of cycles or bars elapsed. (Transport has an internal clock divider in the right click context menu, which defaults to 4 because there are [usually] four beats in one bar. Choose 24PPQN if you are using an external MIDI-CV CLK source.) If you are using Impromptu CLOCKED as your clock source, make sure to turn OFF Outputs high on reset when not running in the context menu of CLOCKED. (Your clock signal should start low, and then immediately go high when playback begins, counting starts at bar 1. When stopped, the clock should return low.)
• Tap the ARM button, or input a trigger from another source (eg. STROKE), to arm recording on next play (or to start recording when already playing.) If you want to do many recording takes, you can wire this from the MIDI-CV STOP output, and it will automatically re-arm when stopped. When already playing, the ARM input is quantized according to your selected Quantize Arming in the right click context menu. This will let you record exactly on the down beat (clock high) of the next bar x1, x2, x4 etc. or you can turn the quantization OFF and record without any delay.
• Tap the PLAY button, or input a trigger from another source (eg. STROKE), to start playing. If recording is armed, recording will start too. Choose whether you want to have PLAY be a toggle button, or to behave as a latch (See Play button is toggle? in the right click context menu). You can wire this from the MIDI-CV START output so that it starts when your DAW Host transport starts.
• Tap the RESET button, or input a trigger from another source, to reset, stop playing, and un-arm recording. You can wire this from the MIDI-CV STOP output and so it would stop when your DAW Host transport stops. By default, a RST trigger is output everytime playback starts or stops. This can be configured in the right click context menu under On Start and On Stop.
• Output a reset signal (RST) from Transport back to your clock generator (optional).
• PGAT is output high for the entire time playing. PTRG triggers a pulse on start and stop.
• RGAT is output high for the entire time recording. RTRG triggers a pulse on start and stop.
• Output PGAT or PTRG to your Clock Generator's RUN input. (PGAT is preferred. For Impromptu Modular's CLOCKED module, set Run CV input is level sensitive in the right click dialog.)
• Connect RGAT to the recorder GATE input, or RTRG to its TRIGGER input.
• The LOOP output is a trigger that pulses at the beginning of every loop of the record length (whether recording or not). You can use this to trigger a sampler so that it synchronizes back to the original clock that it was recorded with.
• In the right click context menu of Transport, set Quantize Arming if you want the recording to start exactly on the next beat/bar x1,2,4,8,16 etc. The arm button will flash while waiting for the next quantized beat in order to start or stop recording.
• In the right click context menu, set Stop on record length if you wish to stop playback after the recording LENGTH counter is reached. (When off, the LENGTH only affects the recording time.)

Here is an example patch that shows Transport hooked up to the host DAW transport via MIDI-CV and set to automatically re-arm the recording on stop for multiple recording takes. The host DAW is set for 120BPM, Transport's internal clock divider is set to 24 PPQN, and the Transport record length is set to 4 bars, so therefore, when its (automatically) armed and you press play, it will send a trigger to start recording, and then stop it after exactly 8 seconds as shown elapsed here:

You can download this as a VCV Rack selection .vcvs

Here is an example patch that acts as a Live Looper platform (see notes inside the patch):

You can download this as a VCV Rack selection .vcvs in several versions: 1) DAW-less where Transport has primary control and 2) Controlled by MIDI-CV for use in a DAW. and 3) MIDI-CV 8 stereo channel version

In this repository is an included tool called wavsplit.sh, which is a BASH script that runs the sox tool to split a 16-channel .wav file into 8 separate stereo .wav files.

• You will need a copy of sox installed (available in any Linux package manager, and probably available on Mac and Windows too)
• The BASH shell. (standard on Linux, and should be on Mac too. For Windows try WSL.)
• Run the script like this: ./wavsplit.sh recording.wav
• The script will check to see if all dependencies are met, and then attempt to split the recording.wav into 8 separate stereo tracks named recording_1.wav -> recording_8.wav in the same directory as recording.wav.

Latch contains two (2) polyphonic CV latching gates ('Flip-flops') with discrete triggers and reset inputs. A trigger on the TRIG input will set LATCH output to +10v. A trigger on the RESET input will set LATCH output to 0v. The inputs and outputs are duplicated as two separate sections, an upper and lower. Each input and output accepts up to 16 channel polyphonic CV, combining both sections offers up to 32 independent flip-flop gates.

Here is a simple example, where Latch transforms any pair of triggers into a persistent ON/OFF gate:

Here is another example problem that Latch helpfully solves:

Impromptu Modular's CLOCKED/CLKD modules have a RUN output that only outputs a trigger when the clock is started AND/OR when stopped (a toggle). The RUN input may be configured to accept a gate signal by choosing the right click context menu labeled: Run input CV is level sensitive, however the RUN output can only be set as a trigger. If you would rather have a single persistent gate that is either high when playing or low when stopped, and you also want to have two discrete play and stop buttons/CV inputs (not a single toggle button), then you can use Latch to solve this:

You can download this as a VCV Rack selection .vcvs

• Connect a trigger button to the first TRIG input of Latch.
• Connect a different trigger button to the RESET input of Latch. In parallel, connect this same trigger button to the RESET input of CLOCKED.
• Connect the LATCH output of Latch to the RUN input of CLOCKED. Right click CLOCKED and select Run input CV is level sensitive and turn OFF Outputs high on reset when not running. The same LATCH output can be used as a "Play mode gate" elsewhere in your patch (attached to the scope for example).
• Press the first trigger button to start the clock. Additional presses will not do anything if the latch is already high.
• Press the second trigger button to stop/reset the clock. Additional presses will not do anything to Latch if the latch is already low (but will still reset CLOCKED again because its connected directly).

The example above only uses the top section of Latch, and only with a single monophonic Latch output. You may connect up to 16 polyphonic trigger+reset inputs and 16 latch outputs per section, for a total of 32 latches if you use both sections. Use the Merge and Split (VCV Fundamental) devices to use polyphony.

Here is a demonstration that uses 20 latches with discrete TRIG and RESET inputs from Pulses:

You can download this as a VCV Rack selection .vcvs

Pulse is a bank of 16 pulse generators: they turn triggers into gates with a single shared clocked length. Using 16 channel polyphony, Pulse has 16 TRIG inputs, 16 GATE outputs, and 16 END outputs. The triggers are quantized to the incoming clock with configurable resolution. The GATE outputs are held high for the duration of each independent pulse. The rising and falling edge of the gates are triggered on discrete RISE/FALL jacks. END outputs are triggered on the clock cycle immediately preceding the end of each gate. A single LENGTH parameter controls the length (1 -> 128) of each gate. All of the gates must share the same length, however they are triggered and held independently of each other. Use the external CLOCK signal, and the built-in clock divider, and pulse will count the exact amount of time to keep each gate open at different times. A shared RESET input will immediately reset all of the gates and the clock.

Pulse is kind of like a smaller version of Transport, but with the addition of 16 independent triggers and gates. It can count clock cycles, like bars of music, or individual beats. It holds the GATE outputs high for the duration you choose. For example, you can use it as the sustain input to an envelope generator, or as a gate input on a sampler. (The pulse itself is always a square wave). The gate interval is configured by the shared LENGTH parameter knob. It has an internal clock divider to configure any common clock resolution.

The display on Pulse has three rows:

1. The length parameter used for all of the gates (in red).
2. The current progress of the top most gate being held. If there is only one gate active (on any output) the display is yellow; If there is more than one gate active, the display is pink (but only shows one counter displaying the lowest numbered active channel).
3. The clock counter / clock divider (in white). (Only visisble when the clock divider is greater than 1.)

The END output triggers at the start of the final clock cycle of the pulse gate, to signal that the pulse is scheduled to end on the next clock cycle. You can daisy chain several Pulse modules together, to fire sequentially, by wiring the END output of one into the TRIG input of another (each Pulse module must share the same clock source, but each can have different lengths). If you were to self-patch the END output back into the TRIG input of the same Pulse module, the pulse gate would loop forever.

In the menu, the triggers can be quantized to the next bar, or x2, x4, x8 etc. With quantization turned on, incoming trigs will wait to start the gate on the clock. With quantization turned OFF, triggers will fire and hold gates immediately, even before the next clock phase, and then hold normally for the entire gate length in addition to that. Thus, with quantization turned OFF, the gate will always be a little bit longer than the length set. For perfect divisions of your clock, always use quantization.

You can configure what to do on a re-trigger event for a gate that has already been triggered and with gate already in progress: there are three choices for the On Re-trigger during gate option in the menu:

• New Trigger - Continue the gate and reset the count to 1.
• No New Trigger - Ignore the new trigger, keeping the original count.
• Reset - Ignore the new trigger, but reset the existing gate on the next clock phase. (This turns each trig input into a toggle switch with clocked time resolution.)

Here is a demonstration of the independent triggers and gates. Just like in the example used for the timing of Transport, this example sets Pulse to a gate of 4 bars. The clock is set for 120 BPM. Assuming that its setup correctly, the timer circuit will watch the gate length time and show it as exactly 8 seconds.

You can download this as a VCV Rack selection .vcvs

You can download this as a VCV Rack selection .vcvs

Range is a polyphonic latched voltage selector. Input triggers to latch the selected voltage, held until the next trigger happens, or until reset.

Range has two selectable voltage ranges, toggleable via the RANGE button:

• 0V -> 10V : Use any of the 11 input trigger jacks labeled 0V to 10V.
• 1V/octave (0V -> 1V): Use any of the 12 input trigger jacks labeled C to B.

A single trigger on RESET will reset all the outputs.

In the following demonstration, Range is used to select four pitches from a chord. It is done in two different ways on the two rows, to demonstrate both 10v and 1v/octave ranges:

You can download this as a VCV Rack selection .vcvs

Negative Harmony inverts music notes around a chosen axis. Select a central note at which point to flip the notes below it with those above it, and vice versa. This technique has been popularized by Jacob Collier and he does a good job of explaining its character in a series of June Lee's videos..

You can download this as a VCV Rack selection .vcvs

The included patch simply routes incoming midi through Negative Harmoy and passed back out to the host midi out. With the default setting of the Axis at C4 this effectively mirrors your MIDI keyboard, such that all the top keys are on the bottom and vice versa. Choose a different axis and this mirroring point will be shifted accordingly.