Martin has spent a great deal of time making his PVC marimba for a Science Olympiad contest. He let dad use the power tools to cut the pipe and wood, but did most of the rest himself. First he had to calculate the lengths of pipes using this formula:

Tube length = (Speed of sound/2*frequency) plus (Tube diameter/2)

Of course, first he had to calculate the speed of sound = (Tube length – tube diameter/2) * 2 * frequency

But first, he had to have a way to get the frequency, and there is a neat Kindle tuner app that shows the frequency and note.

At any rate, without further ado, Martin playing his home-made instrument!

And a photo in case the video is too slow.