Mogwai, Hoxton Square Bar & Kitchen, London

It's sobering to realise that Mogwai have now been on the scene for 15 years. No longer the Blur-baiting noisenik upstarts, they're probably now the elder statesmen of the entire post-rock movement, and they have the pattern baldness to match.

Tonight's show is technically a warm-up ahead of their 2011 tour and they're doing it in one of the hottest, most densely packed rooms on Earth.

It's mostly material taken from their new album, Hardcore Will Never Die, But You Will. Fans needn't worry: it's incredible, powerful and contemplative, trading more on the threat of violence than on violence itself, a study in controlled dynamics. In fact, it's probably some of the best work of their career. Where an earlier Mogwai were too often tempted to meander and lose focus, this older, wiser and more refined band has learned to pace itself, leading to a superb set of songs. They're still long enough to appeal to the musos, but they no longer tip us into a 20-minute post-everything void.

On a few of their new songs, the band experiment with some unexpectedly lovely vocodering effects. Nominal frontman Stuart Braithwaite's delicately modulated voice floats serenely above the tectonics of the music in gentle counterpoint to all the guitar bludgeoning going on underneath.

Of course, they haven't forgotten who they are, and they do eventually uncloak themselves and go nuclear. When they do open the valves, it's to the hoped-for extent: by the end we're engulfed by eddying crescendos.

At their heaviest, a four-man guitar attack on a tiny stage administering wave upon brutal wave of sound, Mogwai are terrifying. Set closer "My Father My King" is a ten-ton case in point, one simple riff repeated with increasing vehemence until it's heavier than the sun. It continues with relentless gusto practically until the blood trickles from our ears from the sheer pressure of sound. Maybe the tinnitus won't be permanent.