Martinù’s final two symphonies sit, Janus-faced, across his later orchestral output. The Fifth (1946) was the culmination of the symphony-a-year series begun in 1942 although its outward demeanour and internal structure and processes are very different to its predecessors. Its tripartite format, however different in design to that of No 3, is the precursor to those of the Sixth (1951-53) and its successors Les fresques de Piero della Francesca and Parables.

Nos 5 and 6 also inhabit radically different sound worlds to each other, the Fifth more outwardly abstract – although there is no doubting the unalloyed joy achieved at the finale’s climax – while the Sixth, as its subtitle suggests, explores deep veins of fantasy. The performances are rather unalike as well, even though both were recorded in Prague’s wonderful Rudolfinum, No 5 live at the 2007 Martinù Festival while No 6 followed last May without an audience.

Both works are splendidly rendered with No 5 best of all, a vivid interpretation benefiting from the buzz of a live performance. Belohlávek gets the balance in the tricky finale just right, letting the mood progression of sadness-joy-determination flow organically and logically. Much as I love Nos 4 and 6, this is the type of performance that convinces me that the Fifth is the greatest of the symphonies. By comparison, No 6, fantastical though it is, seems a mite deliberate and clinical. Both recordings strike me as superior to his previous outings and have better sound than the classic Ancerl. Järvi’s somewhat un-Czech No 6 still edges the top recommendation for me, though in No 5 honours now are even. A richly rewarding disc.