555 Plasma Speaker

The 555 can do anything. OK, that’s become a bit of a trope in our community, but there is quite a lot of truth behind it: this little timer chip is an astonishingly versatile component.

[Alexander Lang] has added another achievement to the 555’s repertoire, he’s used one in the creation of a plasma speaker. Working at Hackspace Manchester, he’s used the 555 as a pulse-width modulator that drives a flyback transformer through a MOSFET, which feeds a spark gap mounted in a lasercut enclosure. The results maybe aren’t yet hi-fi, but it works, and is very audible.

We’ve been following this project for a while, as he’s updated his progress through several iterations. From initial design idea through PCB and enclosure design, to a first working prototype and some audio refinements, and finally this latest post with the spark gap in its enclosure. He is still refining his speaker, so there is more to come

In the video below the break he demonstrates his pulse width modulator, and tests the device using a keyboard as an input.

We’ve only featured one plasma speaker here at Hackaday, but we’ve certainly covered a host of 555 projects. Some are particularly memorable, like this 555-based computer, while others like this AM transmitter and receiver are more fun projects. Browse them yourself, by looking at posts tagged “555”.

Meanwhile in 2012 we noted the passing of its creator, [Hans Camenzind], to whom we 555-heads owe so much.


Filed under: hardware

Leave a Reply

Your email address will not be published. Required fields are marked *