Hip-hop doesn't come easily to DJ Shadow, but neither does he want it to. "I'm sure it would make a better picture," replies the serious, quietly spoken Californian when I suggest it might be a nice change to forego the regulation hood uniform of puffer jacket and beanie hat for the photographer. "But I'm just not confident unless I'm protected as much as possible when I'm doing photos. It's a psychological thing, plus it's a hip-hop thing as well. On the other hand, I don't want you to get the wrong impression of me - this is what I wear all the time."

Such is the trouble small town Josh Davis has to take to evince the urban credibility proper to DJ Shadow, hero of hip-hop.

But it's been worth it. Shadow's gold-selling1996 debut LP, Endtroducing, which, by rights, should have been no more than a diverting slice of leftfield trip-hop, quickly took its position alongside Portishead's Dummy and Tricky's Maxinquaye in a triumvirate of groundbreaking 90s pop albums. A clutch of tracks on Headz (a 1994 compilation on the British and painfully trendy Mo' Wax label) had shown the wider world early promise, but nothing short of a Robert Johnson-style pact with the devil seemed to explain the tectonic sublimity of Endtroducing. And with September's single "High Noon", this month's support slots for Radiohead and the release of an Endtroducing remix (by scratchmeister Q-Bert), the end of 1997 finds Shadow reluctantly nudged into the limelight.

At first sight, Endtroducing plied the usual schtick of 1990s hip-hop - in the copious sleevenotes "all respect [is] due to various innovators... of sample based music" and the album predictably opens in a flurry of scratching. But the absence of gung-ho bravado and lazy sampling in addition to its reliance on structure and mood revealed an album both more and less than the sum of its hip-hop parts. Endtroducing was an ethereal tapestry of strings, voices, woven from 100 per cent sampled music, and propelled by an assortment of stately rhythms. This was hip-hop re-imagined by a revolutionary outsider, less "in ya face" than in your head and heart.

"Hip hop was a remote possibility." The 25-year-old's middle-class childhood near Sacramento, dominated as it was by the moribund AOR tastes of his parents and schoolmates, was a galaxy away from Los Angeles and New York. "Even though I was living in California, I was as far removed from hip- hop as a live experience as someone in any small town." Davis's revelation came in the form of "The Message", Grandmaster Flash's seminal rap hit. " `The Message' was where rap began as an art form for me," he declares.

Starved of hip-hop's vibrant urban culture, this epiphanic encounter inspired in Davis a near religious zeal. "Hip-hop, for me, was never about fashion or hanging with a gang. When I got a piece of vinyl it was all about studying the label, where it was from, who produced it, where it was recorded and who they thanked." Hip-hop became a hand-me-down culture for Shadow, and the effort of absorbing it as and when he could impressed on him an enduring respect for the puritanical virtue of toil. "It took me two hours each way to travel to the studio where I recorded Endtroducing. If it had just been round the block, any old time the going was hard I'd have just gone home. And that's not the way you get really good music - it has to be hard," insists Davis. "It's a pilgrimage in a way."

Devotional fanatics pride themselves on taking "the path less travelled" and so it is with Shadow. Following the mainstream success of commercial acts in the late 80s, the money thrown at hip-hop, he believes, forced it to make an artificial distinction between artists going to hysterical lengths to be considered "real" and the likes of MC Hammer and Vanilla Ice. The result? A contemporary hip-hop scene - the Wu Tan Clan, Rakim, Dr Dre and a few others notwithstanding - impoverished both by the rhetorical excesses of gangsta rap and an incestuous reliance upon overfamiliar 70s and 80s soul and funk samples. "It's a lot easier to promote someone who says controversial things and who gets shot at than it is to market a musical concept," explains Davis.

"Of course, it would be easy for me to take the cool part of "Apocalypse Now" or obvious stuff from Kool and the Gang and slide it in to my records," sighs Davis. "But you don't want to hear the same thing over and over again." To this end Shadow feels impelled, like the anonymous record collectors celebrated on his album cover, to scour long-forgotten record stashes. "It's a secret place I have," he says of a store he visited in the US recently. "I found mummified bats and heroin needles in between records - my hands were getting all cut up digging around for stuff."

He likens the search to archaeology, relishing the thought that the hip- hop fates may have led him to some fetid warehouse for a reason. "Even though I know 90 per cent of the listening public couldn't care less whether I got the beat from a Blue Note Breaks CD or from a basement in Oklahoma City, I know where it comes from." Though he admits it sheepishly, Davis believes that some form of destiny has swelled his record collection to around 50,000 strong. "You stop to think why you found that record and what you're meant to do with it. Sometimes," he muses, "I think things like that happen for a reason."

Mysterious forces were certainly at work two years ago when Mo' Wax impresario James Lavelle insisted that Radiohead's Thom Yorke and Richard Ashcroft of The Verve collaborate with Shadow on the widely anticipated Unkle album project. As Davis recalls, people were wondering whether Radiohead had peaked with The Bends and the prospect of The Verve reforming after A Northern Soul looked unlikely. Though 1997's end finds Radiohead and The Verve vying for the title of band of the year, Davis is relieved that Yorke's and Ashcroft's contributions are in the can: "I'm glad we did it when we did, because I probably would have been a lot more nervous about it this year". The Unkle project, long overdue, has a lot of luck behind it and a lot more hard work ahead - just the way DJ Shadow likes it.

DJ Shadow (Q-Bert Mega Mix) `Camel Bob Sled Race' out 8 December. `Unkle' album expected early next year.