Tuning and Microtonalities

One of my interests is microtonalities/non-standard tunings, so support for such explorations has been included in the library.

There are several ways that tuning data can be specified in the MIDI standard, two of the most common being note pitch-bend and bulk tuning dumps. In this library I have implemented the real-time change note tuning of the MIDI tuning standard. I chose that as a first implementation because most of the soft-synthesizers I use support this standard.

Note, however, that implementation of the MIDI tuning standard is somewhat spotty, so you may want to verify that your hardware and/or software supports it before you spend too much time.

Recently the pitch bend message had been implemented. The advantage of the pitch bend is that almost all software and hardware understand it. The disadvantage is that different software and hardware can interpret the values differently.

The main function to support a tuning change is changeNoteTuning.

Tuning Program

With some instruments, such as timidity, this is all you need to do: timidity will apply the tuning change to the notes. Other instruments, such as fluidsynth, require that the tuning program be explicitly assigned. This is done with the changeTuningProgram function:

Tuning Bank

The tuning bank can also be specified (fluidsynth assumes that any tuning you transmit via changeNoteTuning is assigned to bank zero):

An Example

So, as a complete example, the following code fragment would get rid of that pesky 440 Hz A and tell the instrument to use the tuning that you just transmitted:

track   = 0
channel = 0
tuning  = [(69, 500)]
program = 0
bank    = 0
time    = 0
MyMIDI.changeNoteTuning(track, tuning, tuningProgam=program)
MyMIDI.changeTuningBank(track, channel, time, bank) # may or may not be needed
MyMIDI.changeTuningProgram(track, channel, time, program) # ditto

Using Pitch Bend

Pitch bend is a channel level event, meaning that if you pass a pitch wheel event, all notes on that channel will be affected.

To Do

  • Implement the tuning change with bank select event type.