Thomas Tallis may have written his revered 40-part Spem in alium motet after meeting the Mantuan composer Alessandro Striggio in London in 1567. Perhaps Tallis even took as a model Striggio's own 40-part mass Ecco si beato giorno, which in its final Agnus Dei rises to 60 parts. For centuries, the missing link in this theory was Striggio's lost mass itself; its rediscovery is an astonishing moment in musicological history. Unveiled in this late-night Prom by the augmented Tallis Scholars, possibly for the first time in half a millennium, Striggio's work is a masterpiece; richer and more extravagant than Tallis's more austerely English motet, but more than fit to be mentioned in the same breath as twin landmarks of 16th-century polyphony. To hear Peter Phillips direct the Tallis, followed by Davitt Moroney's compelling rendition of the Striggio, was to be present not just at the choral event of the year but possibly of the decade.
It will be a surprise if Sam Hayden's orchestral work Substratum, conducted by David Robertson, which opened the earlier BBC Symphony Orchestra Prom, will command a hearing in the 26th century. Though this was an interim premiere of the work, consisting only of the final three of its seven parts, its dense textures seemed to cohere only in the hushed final pages.
The two 20th-century American symphonies that followed were in another class. Ives's Fourth Symphony, directed with absolute assurance by Robertson, is the last word in eloquent complexity. The revelation, though, was Bernstein's second, inspired by Auden's The Age of Anxiety. Though it has awkward pages, a performance like this, with Orli Shaham judging the piano part to perfection, makes you think this is one of the great orchestral works of the postwar era.
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