The players of Classical Revolution are not your mom and dad’s classical musicians. Instead of a bunch of old folks in formal wear in rapt communion with the infinite, it’s a bunch of young folks in street clothes getting down with the music.

Down as in low. When I saw Classical Revolution this past March at Silvio’s Organic Pizza on North University, there were two violinists, two cellists, a bass player—Richard Robinson of the DSO, no less—and seven, count ’em, seven violists, including renowned local veteran John Madison and CR founder Charith Premawardhana. Though the violists only played two or three at a time, the ensemble was still distinctly bottom-heavy—and all the funkier for it.

They opened their first set with a rocking Ruslan and Ludmila overture by Glinka. If the ensemble was a bit scrappy at times, well, Ruslan is one mother of a virtuoso overture. But the more important thing is that Glinka’s soaring themes and propulsive rhythms came across with tremendous energy in the young musicians’ hands—and their enthusiasm was infectious.

That’s more or less the point. From the time it was founded in 2006 at the Revolution Cafe in the Mission District of San Francisco, the mission of Classical Revolution has been to “present concerts and non-concerts involving traditional and non-traditional approaches,” as their press release says. What that means in practice is an ad hoc band taking on pieces they may or not have played before in styles they may or may not have ever tried before—and having a blast doing it.

Some pieces in the first set were transcriptions, like the opening movement of Beethoven’s Pathétique piano sonata scored as a stark and angular string septet and Rachmaninoff’s Prelude Op. 23, No. 6, as a swinging, swaying Russian dance. And some were originals like Robinson’s Pork ‘n’ Beans, a collection of tunes and riffs set to funk syncopations with transitions so tricky the ensemble had to stop once.

But that was OK. Everybody on stage and off laughed—and then the music started again. In some ways, Classical Revolution is just a gussied-up sight reading class, and slipups are bound to occur. But in more significant ways, CR is young musicians having fun—and sharing their fun with the audience.

That audience started out as half a dozen people, but by the end of the first set Silvio’s was nearly full. And not just of listeners: more musicians came too—including two more violists.

Musicians are always welcome to join the Classical Revolution “Chamber Jam,” which returns to Silvio’s Organic Pizza on Monday, December 5.