Approach with care, for while the gentler electric expeditions of radical instrumentalists Mogwai could soothe the most fragile of souls, the next second they just might mash your brains to a smooth, pip-free pulp. Ah, marevellous.

Never let it be said that Mogwai are aiming low. In between the classic Iggy quote that opens their second album 'Come On Die Young' and the pointedly titled 'Punk Rock/Puff Daddy Antichrist' that closes it lurks music of a fury and delicacy that makes this five-piece possibly - and on the right night, definitely - the best guitar band operating in these islands today.

Of course, not everyone in rockdom would agree - a fact that the Mogwai team, hunkered down in their PR's office with a sheaf of recent album reviews, fully realise. "Only about five per cent of these understand what we're trying to do," remarks Stuart Braithwaite, main directional rudder, lead guitarist and (very) occasional singer, bemusedly. "The rest either think it's shit or completely get the wrong end of the stick - they just don't get it."

But what, pray, is there to 'get'? "It's hard to explain," Braithwaite admits, pushing the paperwork to one side, "... even to myself. But a lot of people are comparing us to really fiddly prog stuff, and I don't understand that at all. It's much more downbeat than that. Then some people seem to think that very little actually happens in the music, and they see that as a failing. I'm sorry, but I think that's just completely ignorant.

"I don't want to seem bigheaded, but we are competent musicians and we know what we're doing. Everything we do is completely deliberate. Having said that, we don't actually analyse what we do too much - we just get on with it. It's weird to read what people think... really weird. The thing is," he concludes cheerfully, "we don't really think about what our records sound like until they're finished. And then we're like, 'bloody hell!'"

Stuart Braithwaite and bassist Dominic Aitchison formed Mogwai in 1995. After recruiting drummer Martin Bulloch and then-limited but swift-learning second guitarist John Cummings, they released a short series of bewilderingly good vinyl 45s before signing to Glasgow's cool Chemikal Underground label in 1997. An EP, '4 Satin', followed, then a legendarily tired and emotional tour in the company of (temporary, as it turned out) of ex-Teenage Fanclub keyboardist Brendan O'Hare. At last came the band's first LP, 'Mogwai Young Team', a towering feedback tour de force that drew breathless comparisons with My Bloody Valentine, Spacemen 3 and Spiritualised. "We're not too keen on it now, no," their leader sighs today. "There's some good music on there... but it was all a bit too rushed."

The new, more mature phase in Mogwai's history was marked by the recruitment of all-round instrumentalist Barry Burns ("He's really good... good enough to get a job in a wine bar," snipes Braithwaite with a grin. "The first time we played with him in the studio he did that really fast organ intro to 'Light My Fire...' and then stopped and went 'Fuckin' shite!'") Thus freshly remembered, Mogwai arranged to record their second full-length CD in less stressful circumstances than before: at the home studio of Mercury Rev bassist Dave Fridmann in upstate New York.

"The middle of nowhere," expands Braithwaite. "It was ideal, really. We could spend all day recording, then have a few drinks and listen back and talk about the next day. It gave us so much more time to think about things. It was also great to get out and enjoy each others' company again, have a good laugh with our pals - which is basically what it's all about. It's why we chose to do this in the first place, after all."

Mogwai reportedly requested a sound somewhere between the Velvet Underground's challenging 'White Light/White Heat', Nick Drake's delicate, melancholy 'Pink Moon' and Joy Division's 'Closer' - and Fridmann came up trumps. "Dave was tremendous," Braithwaite allows. "He's a professor at a nearby recording college, so he's a boffin with all the studio stuff - but he's also got a real sense of what good music is, as well. He can listen to really badly recorded lo-fi things and hear what's about them. He's really into arrangements, so that's good, and his equipment ideas were great. For instance, instead of ordinary compressors we used these amazing old 1960s radio station broadcast ones that actually compress the whole mix and work in stereo and everything.

"For me, the best songs were the ones we wrote just before we went. Some songs - like 'Ex-Cowboy' - dated back to just after the first Lp so we were pretty sick of them. The fresher ones seemed to come out fresher all round - 'May Nothing But Happiness Come Through Your Door', 'Oh! How the Dogs Stack Up' and the one with the singing on, 'Cody'. Did I have to get drunk to sing it? No, 'cos I felt comfortable with Dave.... although I had to remove the rest of the band from the studio! When I sang with Aidan Moffat (Moffat, of Arab Strap) on the last one" - the song 'R U Still In 2 It' - "I had to get completely obliterated, or I'd never have done it at all..."

So which of these unique tunes will grace our daytime radios? Well, none of them, actually, for in a move that would surely have Led Zeppelin nodding whiskery approval Mogwai have decided not to lift any singles off 'Come On Die Young' at all. "It's not a '4 Real' kind of thing," defends Stuart, "and it's not really a policy - it's just that we think singles should stand on their own. It seems really cynical to use songs as marketing tools, forcing people to buy the same song twice. I'm not criticising anyone who does it... but it's not for us."

It's a sign of true self- belief when lo-fi post punk noiseniks are happy to talk about their stringy craft instead of mumbling scaredly about 'just doing it'. Stuart Braithwaite has studied music, has taught guitar and is convinced that, for beginners, a decent start down twang road is vital.

"I really enjoy teaching," he explains. "The guy who taught me is sadly dead now. He showed me not just scales and notes but also how you can really just enjoy music and how much there is to it. It's a whole new world. We'd be playing Bob Marley songs, making up our own chord sequences, improvising, playing what we wanted. That's how to learn - not 'well', but as yourself. Classical training's all very well but the danger is you'll only be able to do something if you're told exactly what to do.

"On the other hand, it always impresses you when you're wee when somebody's really famous and cool and you find out they can't play! I was really into the Jesus & Mary Chain, these guys in leather trousers falling about who apparently couldn't play - which wasn't actually true, they could play quite well.

"Take the Sex Pistols - I can't believe there's people who think they couldn't play. They were brilliant! I t could have been Slash playing guitar... it was tremendously well done. Then there was Tom Verlaine and Richard Lloyd in Television, who really took virtuoso playing away from the wankers and gave it back to people who had an idea of what to do with it. 'Marquee Moon' is an absolute landmark...

"I do think guitar is really, really important. My favourite players at the moment are David from Ariel M, who I find very inspiring, and a band from America called Chavez who are coming up with some of the most amazing guitar playing I've ever heard. They've got a really bagpipe-like distortion angle. Do I like Hendrix? Absolutely. Actually, we're planning a cover of 'Voodo Chile' with the vocals put through a vocoder. It might not work out, though… our covers often don't. We once tried to do 'Wichita Lineman'' - the Jimmy Web classic, as crooned by Glenn Campbell - and it was a disaster. We were so shit at playing it"

Taking inspiration from films, places visited and, of course, other bands ("Get the new Labradford album!" TGMM is commanded. "Blag it! There's some guitar on it somewhere"), Mogwai members all bring in bits on tape but tend to work on a more structured manner than before. "We jam," Braithwaite explains, "but we do like a framework, a structure, Having said that, you've got to give things room to breathe. I hate it when bands chop and change too much - you're just getting into it a bit and then it suddenly stops."

Mogwai is, of course, a democracy, but Braithwaite will admit to the odd spot of benevolent dictatorship for the sake of practicality. "Someone has to say what songs to play," he points out. "It's good that there are five of us now instead of four 'cos before if two of us said they weren't sure about something, then it would tend to fall by the wayside. We'd drop songs and never play them again because half the band didn't like it."

Live, too, there has to be someone to co-ordinate Mogwai's starts, stops and famously sudden descents into ear-shredding cacophony. "We know what we're doing," smiles Stuart smugly. "There's a lot of 'one, two, three, four' going on - usually by me counting off fingers behind my back...

"The best gigs come when you just forget what you're doing with your hands. It doesn't happen often - the more you learn what you're doing, the more you tend to be aware of what you're doing - but when it's at its best, it's like someone else is controlling things. At the end, you can't remember a thing that happened... except that it was brilliant."

The remarkable Mogwai guitar experience can be yours at any number of alfresco pop events this summer. But even in the quietest moments, do stay away from the speakers. Just in case.