DJ Hero

That means the gameplay's different, too. "You've got scratching, cross-fades, beat-matching in there... All these new elements allow us to play new music you've not heard in Guitar Hero," says Jackson. In fact, DJ Hero features new music you've not heard anywhere, as more than 80 of the 100-plus tracks on the disc are mixes that have never been released before.

Many of these are produced by FreeStyle's in-house team of 16 DJs, but some have been specially recorded by household names such as DJ Shadow, Z-Trip and Jazzy Jeff. The daddy of them all, Grandmaster Flash, talks you through the tutorial. "If you're a fan of those artists, you'll play those mixes and you'll recognise their scratching style, their beat style, their musical selection - which is pretty cool," says Jackson.

You'll also recognise some of the sounds they're throwing into the mix. The two tracks we get to play today feature recognisable hooks from the Jackson 5 and Eminem, and it sounds like most of the songs on the disc will be mash-ups of catchy chart hits and cool beats. It makes a refreshing change to play a music game that doesn't put the emphasis on screaming guitars and thundering drums. And as someone who's more familiar with "I Want You Back" than "I Wanna Be Sedated", I find it easier to get into the rhythm of the song and pull off some of the trickier button sequences.

But just as I hit my stride, Jackson decides it's time to introduce the crossfader. Accompanying the notes scrolling around the screen are solid lines of colour which switch to the left, right and back to the centre at intervals. Your left hand's job is to move the crossfader accordingly. "It's kind of like the first ever driving game for the Commodore," Jackson says. "Dead simple, just left and right."

Except it's not quite so simple when your other hand is simultaneously trying to press buttons and twist a turntable. And when your brain isn't familiar with this sort of thing, and doesn't usually have to multi-task beyond anything more complex than telling your arm not to drop the pint while your mouth says, "Well yes, it all depends on the leasehold."

Having felt confident and comfortable with the button-pressing, I switch to frightened, confused and inadequate when it comes to the crossfader. I fail to switch it fast enough, or even recognise whether it's supposed to be at the side or in the middle half the time. But that's just me - I was rubbish at Guitar Hero the first time I tried it too, and can still only play the Rock Band drums if someone else holds the other stick. Could this be the worst performance of DJ Hero Jackson has ever seen? "I'm not going to lie to you. It's not the best," he says. "But it's over now."

In fact the whole demo has come to an end, which is a shame. As terrible as I am at DJ Hero, the pathetic yet tangible sense of progression experienced over the course of the session did make me want to have another go. And any videogame which immediately makes you want to have another go is, by definition, good. But is DJ Hero so good it'll make you want to invest a hundred quid - even if you get as many goes as you want for the privilege?

At least one thing's clear: DJ Hero is one of the most intriguing and innovative titles in Activision's autumn line-up. It also represents the publisher's best chance of defeating The Beatles: Rock Band as the battle for dominance of the music genre continues. Unless, of course, they're about to announce Guitar Hero: The Rolling Stones.