ELIZA Carthy and Tim Eriksen have been "accidentally meeting on stage every 400-500 years", as Eliza puts it. More truthfully, the Robin Hood's Bay singer and fiddler from England's foremost folk family and the American traditional musician have known each other since meeting as teenagers more than 20 years ago.

Only now, however, have the dream duo with a shared pioneering spirit united to make an album called Bottle. Released this month on Navigator Records, its marriage of hardcore Anglicana and Americana bonds Eliza's fiddle with Tim's electric guitar, banjo and bajo sexto, a 12-string Mexican acoustic bass.

Why now, Eliza? "Why did it we do it now?" she could be heard asking Tim as they prepared for a tour that concludes in York on Sunday at the National Centre for Early Music.

"We did start a little earlier, doing some recordings about two years ago, though didn't use them at the time. We then made rest of the the album, but we forgot we'd done Love Farewell earlier, and we suddenly thought, oh no, we've forgotten something!" Love Farewell duly became the 13th and closing track.

"It all started when we were asked to perform together two years ago in the Czech Republic [at the Folkové Prázdniny festival], so we had to put together a set for that, and we were then offered a tour in the UK, where we ditched some of the original set and brought some new stuff in."

After a show in Exeter, they headed to Dorset for a six-hour studio slot, where they recorded two or three takes of eight songs, choosing the best. They then continued their tour travels, drove to Stirling through an incredible thunderstorm and recorded their Edinburgh concert.

"We've ended up 'studiofying' the live songs and giving a 'live' feel to the studio tracks," says Eliza. "We didn't mess about with too much overdubbing, just a couple of things. Instead we were trying to use sounds that were already there, putting them through interesting filters, so I spent two to three weeks doing that.

"It wasn't trickery or alchemy; we used what we had, and we've come up with something that's neither a live album, nor a studio album. I wouldn't mind doing that again."

The resulting record combines the Copper Family's Cats and Dogs, May Song and Whitby Lad from our shores with Buffalo, Logan's Lament and Castle By the Sea from New England and Southern Appalachia's canon of ballads, love songs, gospel and dance tunes.

All are rendered in a "hardcore" folk style, but what does "hardcore" mean exactly, Eliza? "We're not being deliberately stroppy or challenging, but I'm conscious of the difference between being 'pretty' or 'beautiful', and challenging music can be beautiful," she says. "I don't think anyone else is doing that, being prepared to sound quite scratchy and unpleasant as we do in a beautiful way. I don't have anything against fluffy alternative folkies playing very peaceful songs but that's not me."

Eliza Carthy and Tim Eriksen's Bottle Tour concludes at National Centre for Early Music, York, on Sunday, 7.30pm. Box office: 01904 658338 or ncem.co.uk