A Foil Tweeter, Sound From Kitchen Consumables Jenny List | usagoldmines.com

The world of audio has produced a variety of different loudspeaker designs over the last century, though it’s fair to say that the trusty moving coil reigns supreme. That hasn’t stopped plenty of engineers from trying new ways to make sound though, and [R.U.H] is here with a home-made version of one of them. It’s a foil tweeter, a design in which a corrugated strip of foil is held in a magnetic field, and vibrates when an audio frequency current is passed through it.

He shows a couple of takes on the design, both with neodymium magnets but with different foils and 3D printed or wooden surrounds. They both make a noise when plugged into an amplifier, and unsurprisingly the thicker foil has less of the high notes.