Legendary quartets deserve to split up in style. The Beatles did it with a concert on a roof; the Lindsays do so with a first (and last) collaboration with the Hallé orchestra.

The Lindsays have chosen to bring their 40-year career to a close with a final lap of honour through the Beethoven quartets at the Bridgewater Hall. As a prelude to that, long-term associate John Casken has created a remarkable new musical dialogue for quartet and orchestra.

There aren't many concertos for string quartet in the repertoire, for the reason that it is probably simpler to conceive of a concerto for oil and water than attempt to reconcile such opposed musical forms. Yet Casken's single movement piece is a laudable attempt to meld the mercurial, unconducted sound of the quartet with the regimented heft of a full symphony orchestra.

Entitled Rest-Ringing (a play on words if you omit the hyphen), Casken allows the quartet expansive room to breathe, with the orchestra operating as a sounding board and echo chamber behind it. Perhaps the closest equivalent would be the baroque concerto grosso - though with forces considerably grosser than anything Handel or Correlli conceived of.

With no thematic programme to illustrate, it's essentially a piece of mood music, the mood being primarily one of wistful nostalgia. Mark Elder balances his forces with insouciant grace; only at the end does Casken make a sudden, unexpected movement - a brusque crescendo that can best be described as a valedictory twang. Ultimately, Rest-Ringing is the sound of old ties being snapped.

A rhapsodic account of Wagner's Siegfried Idyll - with the Lindsays in the box seat - formed the ideal, intimate curtain-raiser. The Lindsays have been such a permanent fixture of the English musical landscape over the past 40 years that it's easy to take them for granted. This emotional concert was conclusive evidence why we should not.