# MIDI controller

> A MIDI controller in Python like FL Studio's — channel strips with pan knobs, faders, mute and solo, velocity pads, pitch and mod wheels, and a virtual MIDI port for your DAW.

Source: https://albakore.github.io/pyzed/audio/demos/midi-controller/

(Image: A MIDI controller playing a beat: eight channel strips with faders moving, pads lighting up and MIDI messages in a log)

A controller you can use with any music program: [`examples/audio/midi_controller.py`](https://github.com/albakore/pyzed/blob/main/examples/audio/midi_controller.py).

```bash
python examples/audio/midi_controller.py
```

It has eight channel strips (a pan [knob](https://albakore.github.io/pyzed/audio/components/knob/), a
[fader](https://albakore.github.io/pyzed/audio/components/fader/) with a level meter, mute and solo), eight velocity
[pads](https://albakore.github.io/pyzed/audio/components/pads-and-buttons/), pitch and mod wheels, transport buttons and a
three-octave [piano](https://albakore.github.io/pyzed/audio/components/piano/). **PLAY** runs a beat on the pads.

It plays its own drum kit and synth through the engine, so you hear everything. Switch on
**MIDI OUT** to also send every move to other programs:

| Control | MIDI message |
| --- | --- |
| Fader 1–8 | Control change 70–77 |
| Pan 1–8 | Control change 10–17 |
| Pad 1–8 | Note 36–43 on channel 10 (drums) |
| Piano | Note on / note off on channel 1 |
| Pitch wheel | Pitch bend |
| Mod wheel | Control change 1 |

**Using it with a DAW:**

On Linux and macOS the controller opens a virtual port named **Pyzed Controller**: pick it as a
MIDI input in your DAW. On Windows it uses the first MIDI output found (install a loopback driver
such as loopMIDI to reach a DAW).

## How it is built

```python
def set_level(self, i, value):
    self.levels[i] = value
    self.apply_mix()                              # the engine's mixer channel
    self.send(0xB0, 70 + i, int(value * 127))     # and a MIDI control change

def toggle_midi_out(self, on):
    if on:
        self.engine.open_midi_output(virtual="Pyzed Controller")
    self.midi_out = on
```

`send` writes the bytes to the log on the right and, when MIDI OUT is on, calls
`engine.send_midi(message)`.