[Anthony Garofalo] has made a fancier plasma speaker. Not content with a simple spark, he uses a plasma vortex. To make the vortex, the spark gap is swapped out for an electrode placed in the centre of a ring magnet. The Lorentz force experienced by the arc causes it to rotate rapidly enough round the arc of the magnet’s centre to appear as a continuous sheet of plasma.
The speaker gets its power from an inverter using a flyback transformer driven through a MOSFET by a 555-based pulse width modulator. You can see the result in the video below the break, it’s very impressive to look at but probably not quite ready to sit in your hi-fi stack. The resulting sound isn’t quite as good as that from a stationary arc, but it looks a lot cooler.
This may be the most visually impressive plasma speaker we’ve featured here, but it is not the first. Recently we featured another 555-driven speaker in a wooden enclosure, and back in 2010 we featured a how-to guide with a video for plasma speaker constructors.