Blog How to DIY a Keytar with Cardboard with Multi-Control

How to DIY a Keytar with Cardboard with Multi-Control

A Keytar perfectly combines keyboard and guitar together. So today we will make an ultralight cardboard Keytar. No matter you like musical instrument or not, you will love it!

Check the video here:


Multi-Control board

USB cable

10 x 3-pin inching switch



Male-to-female pin header


Utility knife

Mark pen

Double-sided tape

Glue gun

Soldering iron



Step 1: Draw Out a Keytar


Step 2: Cut the Keytar Boards

Follow the outline to cut the board to get the first keytar board with knife. Then follow the outline of the first to cut to get another board.

Now, we have two Keytar boards at hand.


Step 3: Split the Keys

Split the keys with knife along the gaps and paint the gaps with the Mark pen.


Step 4: Insert Switches to Board

Cut out the keyboard area of the second board, and cut some gaps for the switch, so we need to make sure the gap is the same the switch on the width.


Note: To make sure your Keytar can work after complete, you should make sure the switch position is right under each keys (that is the position should be at the center of the key)


Then fix the switches with glue gun.

And paste two boards together with glue gun or double-sided tape.


Step 5: Solder Switches to Pin Header

Fix the pin header on the back of the Keytar board. Define keys to C, D, E, F, G, A, B, and C+ from left to right, and the keys on the neck to Ctrl 1 and Ctrl 2 as shown.


The pin header is to connect the switches to the Multi-control as shown: C to UP, D to Left… Align the pins on the back of the Multi-Control with the pin header, we can know the corresponding connecting sequence. Then solder the normally-open pins of switch to the pin header via a cable.


Step 6: Connect COM Pins of the Switches to GND

Connect the pin corresponding to Multi-Control’s GND to the COM pins of the switches one by one.


Step 7: Insert the Multi-Control to the Pin Header


Step 8: Download the Code

Visit the wiki page of Multi-Control, you can see the related resources.

Click Here to download the library of the code. Click Sketch -> Include Library -> Add .ZIP Library to include library Joystick and MIDIUSB.



Then go to Github Page and download the code.


Step 9: Modify the Code

The matching of Multi-Control to Switch is different from that in the code, thus we need to modify the pin’s definition.

Here is the mapping of Multi-Control to the Keys.


Thus we need to modify the definition like this:


After modifying, select the board type and port, and upload the code.

Connect the Multi-Control to computer via the USB cable

Get a MIDI software to start your Keytar playing.

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