Finding an appropriate companion piece to Tallis’s extraordinary 40- part Motet is no easy task. As Gabriel Jackson points out in his notes to this disc, the Tallis was neither the first nor the last piece of unaccompanied choral music to be written in 40 parts, but “it remains an unparalleled tour de force of compositional virtuosity”. Rather than combine it with more Tallis or other English church music of the “Golden Age”, Mike Brewer has devised a programme which bookends a programme of a cappella choral works ancient and modern, English and foreign, with Spem in alium and Jackson’s own response to it.

Sanctum est verum lumen itself comes across as an astonishing tour de force, the strands of musical texture cascading through this vast choir with glorious luminosity. These young singers take the work to heart and beyond the almost incredible choral discipline and uniformity of tone that Brewer produces from well over 200 individual voices, there is a real sense of enthusiasm which never intrudes into the technical security of the performance but adds a lovely lustre to Delphian’s luxuriant recording.

Equally impressive are the National Youth Choir of Great Britain’s performances of the two other contemporary works on the disc, Bo Holten’s hypnotic In nomine and Tarik O’Regan’s dramatic I sleep, but my heart waketh.

Perhaps such enthusiasm for modern music which thrives on a big choral sound is understandable, but the earlier music also fares remarkably well in this overblown environment; even where, by the sound of it, reduced forces are involved, there is still a larger number of individual voices per part than we would usually expect.

It is indeed unusual to hear Spem in alium performed with (if my calculations are correct) between five and six voices per part. Whether this is appropriate or not is another matter – most authorities believe the work to have been conceived for eight choirs each comprising five singers – and certainly the sound is decidedly robust, but if one is prepared to put thoughts of authenticity aside, the results are spine-tinglingly spectacular.