#tidal-midi

A TidalCycles module for sending patterns over MIDI.

PortMIDI variant. Should work on OS X, Linux and Windows.

This still is experimental software.

• Installation
  • Prerequisites
  • Install tidal-midi
• Usage
  • MIDI devices on your system
  • Boot tidal-midi
  • Playing Patterns
    • Note length, velocity, and other MIDI CC parameters
  • Custom MIDI Channels
  • Multiple MIDI Channels
  • The default synthController
• Supported Synthesizers
• How to write your own synth mapping
• Automatic bootup in Emacs
• Known Issues

Installation

Prerequisites

Depending on your operating system, you will need to install some prerequisites first.

All Systems

tidal-midi requires the latest version of tidal. Run these two commands in your terminal to install the latest version:

cabal update
cabal install tidal

Linux

Run the following to install libasound2-dev and libportmidi-dev:

apt-get install libasound2-dev and libportmidi-dev

Mac OS X

Install PortMIDI:

brew install portmidi

Install tidal-midi

Simply do:

cabal update
cabal install tidal-midi

Note: On OS X with GHC 7.10 it is necessary to reinstall PortMidi again with frameworks correctly linked:

cabal install portmidi --ghc-options="-optl-Wl,-framework,CoreMIDI,-framework,CoreAudio" --reinstall --jobs=1 --force-reinstalls

Usage

This guide assumes you are already familiar with Tidal and creating patterns with samples.

Get the names of MIDI devices on your system

In order to use tidal-midi you will need the exact name of a MIDI device on your system. You can get a list of MIDI devices on your system by running some code in a regular .tidal file.

Assuming you're using the Atom editor, create a new file and save it with a .tidal extension (e.g. midi-test.tidal). Then, type the following in the editor:

import Sound.Tidal.MIDI.Context

displayOutputDevices >>= putStrLn

Evalulate both of those above lines separately using Shift+Enter in Atom. After evaluating the last line, it will output a list of MIDI devices in your editor (in Atom, at the bottom output panel).

After listing MIDI devices on your system, take note of the device name you will use. Devices names are case-sensitive.

For the purposes of this guide, we'll assume your device name is "USB MIDI Device".

You only need to do this step whenever you want to get a list of devices. Once you take note of your system's device names, you don't need to perform this step ever again (unless you acquire a new MIDI device).

Boot tidal-midi

Make sure you're currently working in a file with a .tidal extension in your editor (it could be the same file from the device list step above). Then type these three lines of bootup code:

import Sound.Tidal.MIDI.Context

devices <- midiDevices

m1 <- midiStream devices "USB MIDI Device" 1 synthController

Evaluate each of those lines (use Shift+Enter in the Atom editor). Now Atom is ready to run MIDI patterns using m1.

In the last line of the boot code above, the last three parameters are the most important:

• "USB MIDI Device" is the name of your device
• 1 is the MIDI channel number
• synthController is the type of synthesizer code to use (you can use custom ones)

Playing patterns on your device

The following code will play a very simple pattern on middle-C:

m1 $ note "0"

Above, the note param indicates a MIDI note, where 0 equals middle-C. The following pattern plays a major scale:

m1 $ note "0 2 4 5 7 9 11 12"

Alternatively, you can use midinote to explicitly use a MIDI note from 0 to 127:

m1 $ midinote "60 62 64 65 67 69 71 72"

You can use normal TidalCycles pattern transform functions to change tidal-midi patterns:

m1 $ every 3 (rev) $ every 2 (density 2) $ note "0 2 4 5 7 9 11 12"

Note length, velocity, and other MIDI CC parameters

Note length and velocity are controlled using the dur and velocity parameters, respectively.

The value of dur is given in seconds:

m1 $ note "0 2" # dur "0.05 0.2"

m1 $ note "0 2" # dur (scale 0.05 0.3 $ slow 1.5 tri1)

Alternatively, the legato parameter tells Tidal to scale the note duration to fill it's "slot" in the pattern. For example, the following will give four notes each a quarter cycle in duration (values of legato greater or less than one will multiply the duration):

m1 $ note "0 1 0 2" # legato "1"

velocity has a range from 0 to 1, and equates to MIDI values 0 to 127:

m1 $ note "0 2 4 5 7 9 11 12" # velocity "0.5 0.75 1"

m1 $ note "0 2 4 5 7 9 11 12" # velocity (scale 0.5 1 $ slow 1.5 saw1)

The synthController has some params that support MIDI Change Control messages, such as the mod wheel:

m1 $ note "0 2 4 5 7 9 11 12" # modwheel "0.1 0.4 0.9"

Details about the default MIDI CC messages can be found in the default synth controller section below.

MIDI CC params can have decimal values in the range 0 to 1, which map to MIDI CC values 0 to 127.

Custom synthesizer implementations may implement additional MIDI CC parameters. Please refer to the supported synths for more information.

Custom MIDI Channels

Let's review this line from the boilerplate code above:

m1 <- midiStream devices "USB MIDI Device" 1 synthController

The 2nd to last parameter on that line indicates the channel number. Let's say your device is running on channel 7. You can specify channel 7 by changing the 2nd to last parameter:

m1 <- midiStream devices "USB MIDI Device" 7 synthController

Multiple MIDI Channels

tidal-midi supports devices with multiple channels so that you can create patterns on each channel separately:

m1 <- midiStream devices "USB MIDI Device" 1 synthController
m2 <- midiStream devices "USB MIDI Device" 2 synthController
m5 <- midiStream devices "USB MIDI Device" 5 synthController

m1 $ note (run 4) # velocity "0.5"
m2 $ note "0*2 5 7" # dur "0.1"
m5 $ midinote "36 60"

Note: at the time of this writing, multiple channels can cause scheduling problems if the synth controller's latency is too low. This is mainly an issue for tidal-midi developers to improve, but users may be impacted. Latency values can be increased by modifying the synth controller's source code (e.g. in SimpleSynth.hs), then re-compiling tidal-midi with cabal install.

The default synthController (a.k.a "simple synth")

The simple synth comes with simple MIDI parameters, that any device should understand:

• modwheel (MIDI CC #1)
• balance (MIDI CC #8)
• expression (MIDI CC #11)
• sustainpedal (MIDI CC #64)

All of these parameters map the given values from 0..1 to MIDI values ranging from 0..127.

You can use all of these parameters like the familiar synth parameters in TidalCycles:

m1 $ note "0*8" # modwheel "0.25 0.75" # balance "0.1 0.9" # expression (sine1)

All tidal-midi synthesizers "inherit" from the "simple synth" and automatically expose these same parameters.

See the section below on Supported Synthesizers for details on custom controllers for popular hardware synthesizers.

Supported Synthesizers

A variety of custom mappings have been created in tidal-midi for popular hardware synthesizers. Click on a device below to get details on its usage:

• DSI Tetra
• Elektron Analog RYTM
• Korg Volca Bass
• Korg Volca Beats
• Korg Volca Keys
• Roland System-1M
• Synthino
• Waldorf Blofeld

How to write your own synth mapping

Interested in using tidal-midi with your own synthesizer? Please read the guide on Writing a new synth mapping.

Automatic startup in Emacs

Within your tidal.el script, locate the function tidal-start-haskell and add:

(tidal-send-string "import Sound.Tidal.MIDI.Context")

after

(tidal-send-string "import Sound.Tidal.Context")

Additionally you will have to add lines to import the synth you want to control via MIDI, e.g. (tidal-send-string "import Sound.Tidal.VolcaKeys") as well as the initialization commands for streams:

(tidal-send-string "devices <- midiDevices")
(tidal-send-string "t1 <- midiStream devices \"USB MIDI Device\" 1 synthController")

The above code adds the MIDI device "USB MIDI Device" and controls it via MIDI channel 1. With this set up you will be able to use it via e.g. t1 $ note "50"

Known issues and limitations

• SysEx support is there but really limited to work with the Waldorf Blofeld