Remember the six-foot tall speaker from Back to the Future movie into which Marty disappears later to emerge in a pile of bookshelf? That very speaker was the inspiration for two University of Wisconsin students, Kyle Hanson and Dan Ludois for their PhD thesis with help from their friends Justin Reed, Adam Shea, Chris Wolf and Micah Erickson. Called the Giant Speaker, this project justifies its name very well with a huge 8’x8’ speaker cabinet having a coil driver fabricated by hand with three layers of 18awg wire wound onto G10 form attached to a fiberglass disk for support. Fitting in the magnet and back-iron layout was a challenge with the funded budget limit of $600 making it even more difficult but they managed to do it incredibly by placing 24 Neodymium magnets and welding steel to the iron pipes for added support.
Once all the things were put into place the next step was to test the speakers and to do it they were driven with 20kW PWM voltage sourced invertor powered by 400V DC power supply. Thereafter the amplifier was connected to gadgets like iPod, bass guitars and Matlab audio scripts to find out that the speakers work best at frequencies of 5Hz to 50 Hz making them a powerhouse for deep enthralling music output.