The “Quadrum” is a percussion instrument, like a Quad Drum from a marching band, made from wood, four plastic bowls, plastic sheeting, rope, a towel, nails and glue.

It is a member of the percussion family because tapping the top of the bowls with a wooden stick, or your hand, causes them to vibrate, producing its sound.

The different size bowls affect their sound. The larger the bowl, the lower the sound and the smaller, the higher.