This is a widely viewed video on YouTube showing a demo of a plasma speaker prototype. This set-up uses a supply voltage of 50 V DC but has a high voltage output of up to 60 kV.
Unlike conventional speakers that produce sound waves by mechanical vibration, plasma speakers do not have moving parts. Instead, they produce sound by varying the intensity of the plasma. The varying plasma intensity creates a varying air pressure in the arc, which produces the compression waves in the air that the listener hears. Modulating the intensity of the plasma properly results in the desired music.
