This is how my prototype looks like right now. The Kalimba has a built in Piezo Pick-Up from which the signal goes directly into the Bela board. The board itself is attached on the left side of the Kalimba. On top of it the touch panel is mounted right in the middle to be interacted with your thumbs. To the right there is a Push-Button and a potentiometer. In the top left corner, you can spot the red accelerometer and another potentiometer.