A concerto for choir by any other name, Richard Strauss’s Deutsche Motette has a good claim to being the hardest piece of tonal music in the choral repertoire. Splitting its singers into 20 parts, stretching them across a four-octave range and climaxing in a fugue of monumental complexity, it’s a work not often recorded and still less frequently heard in concert. Strauss’s mystical ecstasy is a world away from the soft-focus salon piety of Schubert’s Gott ist mein Hirt and Brahms’s Lutheran chorale motet O Heiland, reiss die Himmel auf, which bookend a broad-ranging collage disc of German Romantic choral works.

These are young voices from two discrete ensembles, and their blend doesn’t approach the hazy vocal mesh of either the Danish National Radio Choir or the superb Latvian Radio Choir recordings. Control is also at issue; the tensions and climaxes of Strauss’s epic-in-miniature are the product as much of restraint and denial as of release. When the singers give so much, something, paradoxically, is lost here. A quartet of professional soloists amplify but never obscure choral textures that maintain impressive clarity through the dense contrapuntal writing.

While Rheinberger’s pillowy Abendlied feels similarly overworked, the frank, forward tone of this ensemble softens the academic rigidity of the Brahms and makes a surprise highlight of Peter Cornelius’s Liebe, with its carefully contrasted sequence of moods and tone-colours. A fortepiano cameo in the Schubert offers aural respite from so much richness – the welcome jangle of secular society briefly obtruding into the German Romantic world of mystical abstraction.