SOMETIMES there is a reason for rarities. Purcell threw off the comforts of royal patronage in 1690 and plunged into the commercial theatre to write incidental music for plays.

His first new venture – Roger North, with his tongue only slightly in his cheek, called it a ‘semi-opera’ – was Dioclesian, based on a play by Massinger and Fletcher. But the only part of Purcell’s music regularly heard these days is the concluding Masque.

So the opportunity to hear the complete score on Saturday, conducted by Peter Seymour, was not to be spurned. Jason Darnell declaimed Andrew Pinnock’s mildly flippant, rhymed digest of the plot, which charts a soldier-hero’s rise from the ranks to become emperor.

But in truth Purcell’s music has only flimsy relevance to the play.

It was pleasant enough before the interval, odd glints of inspiration among plenty of Baroque music-by-the-yard. This included recorders being playful or sensuous, and trumpets bursting into fanfares.

The masque was on a different level, a variety of moods from elegiac to buffo neatly conveyed by soloists from the choir, the best of them hardly using their copies or moving their torsos. Especially promising were tenor Jonathan Hanley and mezzo Rachel Wyllie, while Sarah Holland’s soprano was a beacon of clarity.

The band, spearheaded by the Fitzwilliam String Quartet, was tirelessly idiomatic. A mixed bag, then, not Purcell at his most dazzling, if certainly worth an airing. It will probably remain a rarity.