CROOKED Still, the Bostonian fusion of rock energy and old-time mountain music, have played Scotland and Ireland, but never England since forming in 2001.

This wind-swept month they put that right, promoting their second album, Shaken By A Low Sound, on a six-date tour that visits the National Centre for Early Music in York on Wednesday.

"There's sort of two reasons for that album title, " explains double bass player Corey DiMario. "One is that it's from the only original lyric on there, in Mountain Jumper, written by our cellist, Rushad Eggleston. There are a lot of wild lyrics in that song that are spoken very fast.

"Then we also thought that because we have both cello and double bass, we have a low sound that's a contrast to the old string bands, who have a higher instrumental range. So it seems to sum up our music pretty well."

The American band, with roots in the New England Conservatory and Berklee College of Music, are best described as an alternative bluegrass group on a mission to bend the boundaries of traditional music. As their website puts it: "Here's the catch. No electricity.

No drums."

"The 'no electricity' part is a little misleading because we view ourselves as a band with the energy of rock'n'roll, but it's all acoustic, string-based music. We try to keep it current with who we are, with the music we're listening to, without doing it in obvious ways. So we don't add modern elements of guitar and drums, but we do add energy and our instrumentation is novel, " says Corey.

"We're not overtly political in the way that Bruce Springsteen, doing his Seeger Sessions legacy, is an activist first and a musician second. For us it's less of a political thing; we love old string music and we're just doing it in a different way and bringing it to people who don't know it."

Crooked Still play National Centre for Early Music, York, Wednesday, 7.30pm. Tickets: £12.50 on 01904 658338.

Shaken By A Low Sound is released now on Signature Sounds.