Michael Zbyszynski has made a detailed tutorial on how to make homemade spherical speakers, using IKEA salad bowls and cheap speaker elements. The speakers look great, and apparently sound ok, so this would be interesting to do in a music tech course.

New publication on our Cheapstick music controller: {width=“600” height=“315”} Reference: A. R. Jensenius, R. Koehly, and M. M. Wanderley. Building low-cost music controllers. In R. Kronland-Martinet, T. Voinier, and S. Ystad, editors, CMMR 2005, LNCS 3902, pages 123–129. Berlin Heidelberg: Springer-Verlag, 2006. (PDF from Springer) **Abstract: **This paper presents our work on building low-cost music controllers intended for educational and creative use. The main idea was to build an electronic music controller, including sensors and a sensor interface, on a “10 euro” budget.