Hit play on this new recording of Britten’s A Ceremony of Carols and you’ll get a shock. Benjamin Britten may have approved Julius Harrison’s 1955 TrATB arrangement of his upper-voices work (though archival evidence suggests he later regretted this decision) but very few choirs have taken the opportunity to record it, making this a fascinating, if not always entirely persuasive addition to the catalogue.

Clare’s new account joins just three others. The idiosyncratic performance by the Boni Pueri on ArcoDiva (2004) has its charm (particularly the fine treble solos), but the Choir of St John’s College, Cambridge, under Andrew Nethsinga offer what has been, until now, the definitive recording. The contrast between St John’s boys and Clare’s sopranos is just the beginning of two markedly different approaches.

Perhaps surprisingly there’s far more obvious muscularity of tone from Clare. There’s an irrepressible energy and earthiness to their performance that sometimes threatens to overwhelm the music’s simple shapes. We lose the transparency of texture John’s manage to preserve even in this arrangement, and text becomes muddied and obscured in the resonance and sometimes the sheer volume of the recording. These are more door-to-door wassailers than prim chapel carollers.

Both the energy and the slight lack of control continue through the rest of the repertoire – carols and anthems by Britten, with guest appearances from Bridge, Holst and Ireland. It suits the rough-hewn architecture of A Hymn of St Columba and the declamatory Jubilate Deo but becomes more problematic elsewhere – in the fragile A Hymn to the Virgin, where we lose that sense of shimmering otherness, of a conversation across the ages between the two choirs; in Ireland’s The Holy Boy, where the unison melody line too often scatters into individual voices; and in Holst’s This have I done for my true love, which pushes almost to the point of distortion in its final climax.

Shattering stereotypes of polite Oxbridge singing, there’s an exciting, no-holds-barred conviction to the singing here. Whether it is shown to best advantage in the carefully polished precision of Britten’s Christmas sequence is another matter.