I made this box for my music project to our school. This is only tutorial for the box, no for playing melody. It´s based on serial connected switches.
You will need:
Some wire
6x switch
1x LED
1x 330 ohm resistor
5x 2000 ohm resistor (etc.)
1x 10 000 ohm resistor
1x plastic box
small piece of prototyping board
Step 1: Making a wire
First you need to prepare the connecting wire. Take three wires, three pins and a piece of prototyping board with prepared lines of conductive material. I chose this type: the middle pin is analog value and others are VCC and GND.
Step 2: Prepare the box
Take the front side of box and make five holes (i use my soldering iron for it 
) Put the switches to the holes.
Then take a top part of the box. Make there two holes. One for placing ON/OFF switch and one for LED (power indicator) .
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