Pierre Boulez brought his Répons here for its first — and, so far, last — hearing in the spring of 1986. It took another 14 years for a recording of the work to appear, in Deutsche Grammophon's 20/21 Series, which, the way things look now, might be the last significant project in an industry bent on phasing itself out of relevance. Two performances took place, in a basketball gym on the UCLA campus, because this is not music designed for a concert hall, with an audience facing performers through the invisible proscenium wall. It is music to be engulfed in; it tells you to let your spirits wander through its vast spaces, and beguiles those spirits with the sounds of a new world, a new millennium. From the recording, even in a room properly set up for “surround,” that dimensionality doesn't quite happen, although the miking has been done with care and imagination. If you're waiting for the next live performance, don't hang by your thumbs.

Like many of Boulez's later works, Répons went through many gestations, first revealed as a work of 17 minutes, gradually growing to its current (not necessarily final) 42:31. The basic plan has remained. The music is flung into a large performing space from sources set around that space — pianos, harp, vibes, xylophone, all computer-processed in real time. These “respond” to a larger, unprocessed ensemble (Boulez's great Ensemble Intercontemporain from IRCAM, his Paris-based electronic lab) in the middle. The “response” idea happens on several other levels, the interaction of musical textures not unlike the events in a Bach fugue, the interplay of contrasting thematic material similar to that which Beethoven or Schubert might employ. Some of this is fairly abstruse; nobody has ever accused Boulez of easy listenin'; what it all comes to, however, is an exhilarating sweep of sound, much of it a glorious jangle, all of it a vast sonic panorama. Some of this music is thrilling beyond words: the opening minutes, for example, which build relentlessly ahead through a hair-raising sequence of trills, culminating in the gut-grabbing first entry of the electronic forces. At UCLA, that moment just lifted you out of your seat; the marvel of the recording is that it happens there, too. In New York, on the same tour, the Times found it “a tired set of ideas in a shiny new box . . . from IRCAM's electronic Cuisinart.” Oh well . . .

The masterpiece by, arguably, the dominant musical figure of the last 50 years, Répons belongs in that small company of between-centuries works that loom as both summation and beginning. It deals in equal and, therefore, encouraging proportion with the expressive potency of “pure” music and the horizons portended by the facilitations of technology. If not the music of the future, it is certainly one of them.

LA Weekly