The towers are giant Tesla coils, named after for the Serbian-American who invented them in 1891. 'The electrical arcs are vibrating the air and creating sound waves.'

'I think that is the hardest thing to convey to people who don't see it in person,' says Joe DiPrima, one of the founding members of ArcAttack and frequently the man playing the lightning guitar. The guitar player's dancing fingers might control the music, but the notes themselves come from the bolts let loose by the twin towers. This overpowering display is a typical performance for the Austin, Texas-based group called ArcAttack. As he does so, forked tongues of lightning reach out from two towers flanking the stage and strike him. Helmeted like a knight, draped in what appears to be chain mail and wielding an electric guitar, the figure plays the first few crackling chords of his set. In the center of the stage, awash in blue and purple light, a figure steps forward.

The reverberations of the announcer's amplified voice fade into the darkened auditorium, and the last few cheers from the crowd are cut off by a sizzling buzz. ArcAttack's lightning guitarist wears a protective Faraday suit.

Tesla coil sound effect