Glasgow Royal Concert Hall

Keith Bruce

If the diversity of the music that has brought capacity houses to Glasgow's big hall during this year's Celtic Connections has exceeded the festival's previous two decades, no other concert will take the palm for filling it with as much sound.

For surely the youngest crowd Celtic Connections will have assembled this year - and one entirely untroubled by the appropriateness of the music to the supposed style of the event - this was a coup for the event that it could not have predicted. Because without a shadow of a doubt, Mogwai's moment has now come. The new album, Rave Tapes, being the set that has surely catapulted the band into the major league.

It seems a most unlikely Glasgow success story: a band that has none of the showbusiness and style that has traditionally been part of the recipe for success for outfits from Scotland's biggest city. Makers of visceral, sonically precise, instrumental progressive rock music for the 21st century, the changes in what they do have been stealthily incremental: some keyboards and the occasional vocal to augment the variegated guitars with additional colour, increasing use of electronics and computers, the addition of different gradations of crescendo and diminuendo to the trademark crashing contrasts of dynamics.

This set majored on the last two albums, and Rave Tapes set the visual tone for a use of lighting that referenced rave culture and was, in fact, the most showbiz they have ever looked. That matched a sound mix that combined subtlety with the brilliantly, if not impairingly, loud - but I was near the back.