It's the quiet ones you have to watch. Poor old Ed Hughes had two shows booked in and ticket sales were going so badly, he had to cancel the second show.

Then, out of the blue, the gig appeared on the front page of The Independent. Suddenly, people were clamouring for tickets but it was too late for most - and what a treat they missed.

A site-specific response to Teruyoshi Yoshida's shimmering installation, Surface Of The Lake, as a classical concert, this was a first for the Fabrica gallery.

An exciting and unexpected collaboration between composer Hughes and artist-in-residence Pendle Poucher, it combined a six-piece chamber ensemble consisting of a harp, marimba, clarinet, violin, cello and flute with a multi-speaker sound system and improvised live sound capture.

Exquisitely staged and lit, Yoshida's work gained a magical quality less obvious in daylight, while small beneath Fabrica's high, vaulted ceiling, Chroma played with an unabashed and infectious passion. Reminiscent of Steve Reich, the notes flowed together in a mesmerising and beautiful stream, Pendle's subtle, sonic interventions adding an extra layer of texture and space.

A fine example of the hidden gems the Festival can occasional produce, a huge standing ovation came as no great surprise. More, please.