When the 20-year-old Henry Purcell penned his Fantazias and In Nomines (they survive in a single autograph volume from 1680 in the British Library) he was probably thinking neither of posterity nor popularity. After all, the contrapuntal fantasia (including the In Nomine, a special fantasia built on a cantus firmus derived from Taverner’s Missa Gloria Tibi Trinitas) was by this time not only old-fashioned; King Charles II hated it.

Chelys Consort of Viols

So why lavish so much evident care and creativity on such a recherché form? Well, you could ask why countless music students are still required at one time or another to write a five-voice fugue in triple counterpoint.

“It has been suggested that the Fantazias are no more than contrapuntal studies devised by the composer as intellectual exercises and possibly as means of honouring his forebears,” writes Chelys Consort’s Ibrahim Aziz. He also points out that “the ranges of the parts are not always...