Why multiple pianos ar all? Good question. This Prom demonstrated that multiple pianos are not an eccentric novelty. Pianos are percussion instruments with a huge range, which can create a more rapid sequence of sounds than some others. Multiple pianos can create intricate patterns, opening up new possibilties of textural sound.
Nor is it every day you see four pianos nose to nose! Or four pianos backed by large choir, percussion and solo singers. Prom 33 was a special occasion that won't come round too often. Not many halls can even supply four pianos, much less four with complementary tones.
George Antheil's Ballet mécanique is an icon of modernism, seminally important. Read what I've written about it and hear various clips HERE. It 's been heard at the Proms at least twice since 1995. This time we had the miniature version for four pianos, (there were six in 1999 and 2 player pianos). Even with pianists as good as John Constable, Rolf Hind, Ashley Wass and Tom Poster, this was never going to be quite as mind blowing as Ensemble Modern. No propellers or sirens, either. The sound effects came off a laptop, which is pretty basic these days. By Ballet mécanique standards this was Antheil tamed and smoothed out. It was fun anyway, but for the full experience, get the Ensemble Modern recording which has other works by Antheil whose time has not yet come but should.
Ballet mécanique is manic exuberance, but Béla Bartók’s Sonata for Two Pianos and Percussion is a masterpiece of sophistication. This is a four-way conversation, between two pianos and two percussionists, so keys, tones and rhythms weave maze-like complexities. Sometimes Philip Moore is dominant, but Simon Crawford-Phillips' persistence wins out. The percussion voices are naturally more varied and sometimes come close to taking over, but Colin Currie and Sam Walton are too skilled to disturb the finely poised balance. Piano/percussion quartets are never going to replace string quartets because there just isn't the repertoire, but this performance showed that the players interacted as deftly as any quartet whose members play together regularly.
There are many reasons why Ballet mécanique and Stravinsky's Les noces get programmed together. If you're hiring four pianos, you might as well use them all evening. More seriously, both operate on the principle of circulating perpetual motion. Les Noces isn't cantata, far less an opera, because the solo singers function as part of the orchestra. It's a ballet, and the dancers are the ones telling the story. The voices narrate. They aren't characters, as such.
Without dancers, the role of the singers doesn't change. What was good about this performance was that Edward Gardner didn't treat it as quasi-opera but as music that integrates soloists with choir and eight instruments, four pianos matched with four percussionists. Again the formal structure matters: folk dance is a kind of ritual. It's as if the music germinates the dance. Much can be made of the texts, but they work as part of the music, sound, the angularity of the language expressed in the blocks of sounds. Obviously meaning comes into it, but I wonder if that's over-estimated in this case, since the wedding itself is a symbolic ceremony which will continue to exist long after the protagonists are gone.
As for John Adams's Grand Pianola Music, it's hard to judge a performance of music you don't like, positive or negative. I'm hardly anti-new music but I really couldn't get this. So I'll just try to explain what I felt. It's no reflection on the performers good or bad. At first this seemed interesting, rather like the mesmerizing effects of chant, where suddenly repetition takes on a life of its own. Later, Adams starts elaborations which are quite nice but seem more like a backdrop to something else. Perhaps his operas work because they have such overwhelming themes that the music fits round them, rather like film music fits round a film. Huge, sustained applause, so probably the fault is in my ears.