How to make a paper GarageBand MIDI controller
Create a MIDI paper controller
Step 1 Upload the MIDI interface code to the Touch Board
If you haven’t set up your Touch Board, then check out the setup tutorial. Upload the “Midi_interface” code to the Touch Board, making sure that you have selected “Bare Conductive Touch Board (USB MIDI, iPad compatible)” under Tools -> Board.
You can test the code by touching an electrode to see if the ‘L’ LED lights up red on each press. If it’s working, turn the Touch Board off and disconnect it from your computer.
Step 2 Connect the Touch Board to GarageBand
In order to set up the Touch Board with an iOS device, you need the Lightning to USB Camera Adapter. Connect the Touch Board to the USB Camera Adapter and the Camera Adapter to the device. Open the app on your device and create a new project by selecting “Smart Piano” in “Keyboard”. Make sure that you can hear the audio of your device.
Turn the Touch Board back on. In GarageBand, it should detect the MIDI input from the Touch Board. Test the connection by running your finger across the Touch Board’s electrodes. You should hear the sound of the keyboard inside GarageBand!
Step 3 Create a keyboard with Electric Paint
With the Electric Paint, you can create your keyboard, which is going to be your MIDI controller, and paint up to 12 keys or buttons that you want to use in GarageBand. The design of your keyboard is up to you, you can be as creative as you want and instead of painting lines, you can paint circles or triangles.
Step 4 Connect the keyboard to the Touch Board
Before you connect the keyboard to the Touch Board, make sure to turn the device off. You can connect the keyboard to the electrodes of the Touch Board either by cold soldering or with crocodile clips. With the keyboard connected, turn the Touch Board back on and try touching a key, you should hear the corresponding sound in GarageBand. If you want to change the setup and connect an electrode to a different key, you need to turn the board off again, before changing the connection.
Step 5 Changing the notes
The benefit of designing your own keyboard with Electric Paint is that you can create an audio interface that makes it easier to play a melody by just using the necessary notes. So if you want to play only 3 notes, you can just paint 3 buttons. The default code for the Touch Board is set to play a scale from C3 to B3 in semitones. If you want to change the notes, you need to edit the code. Use this reference to check which number corresponds to which note.
Step 6 Changing the instrument
The default instrument on GarageBand is the “Grand Piano”, but you can just change the musical instrument to something else you would like to play with your controller keyboard. Note that a percussion instrument uses a different MIDI note number system than other instruments, as they use percussion sounds instead of notes. You can find an overview of which number corresponds to which percussion sound here.