A practical electrostatic loudspeaker. By Akilaa (Own work) [Public domain], via Wikimedia Commons. A practical electrostatic speaker uses a flexible film that is as thin and light as possible as ...

Most noise-blocking headphones fall into two categories: they use some kind of material to absorb or scatter noise, or they use active cancellation that creates a signal to oppose the noise signal.

An electrostatic loudspeaker uses a thin plastic diaphragm residing between two perforated metal sheets (the grids or stator plates). The audio signal is applied to the grids out of phase.

Warwick Acoustics' electrostatic speaker uses 90 percent less energy and saves up to 20 miles of range. But on which EV will ...