CLASSICAL: Stimmung, The Great Learning QEH

The late Cornelius Cardew didn't accuse Karlheinz Stockhausen of "serving imperialism" until after the two works performed in last Sunday's programme were written. But in 1968 these leading representatives of "experimental" and "avant-garde" musics would have already made uncomfortable bedfellows in concert.

Stockhausen's Stimmung takes long hours of professional dedication to prepare and, on this occasion, it took 84 minutes to perform. Its static harmony - a B-flat ninth chord - is set in vibration by vocal techniques involving methods of overtone-production akin to those found in the chanting of Tibetan monks, and these are accompanied by the extensive reciting of magic names and some poems of the composer's own. Cardew's The Great Learning, for all its Confucian basis and mantric repetitions, is a more down-to-earth blueprint for improvising musicians of any degree of technical skill.

All six members of London Sinfonietta Voices performing Stimmung also joined in "Paragraph 1" of The Great Learning: itself an indication of changing times. They mixed with a few experimental diehards and other sympathetic professionals to form the two groups that together introduce the work with the prehistorical clatter of stones and later, separately, alternate the chanting of a Confucian text with whistling of various sorts, solo whistlers emerging in turn from the ensemble to improvise.

"Paragraph 1" also, though, requires the professional skills of an organist, Michael Chant, who has an extended solo demanding weights to depress keys for long periods, and also provides a backdrop to the other activities, periodically playing a Chinese bell. The text was projected with commitment and clarity and the seven whistlers - playing recorders and assorted whistles and pipes - exhibited an enjoyable variety of approaches to Cardew's graphics, ranging from playful to intense. Even at 38 minutes (longer than advertised), this revival suggested that Cardew's seven-part, seven- hour epic is much more than an old curiosity.

The new version of Stimmung emphasised the play of personalities as arguably just as much a part of the work as the more sober meditations suggested by the ritualistic semicircle of singers and the dimmed auditorium. The decision - possibly unique - to leave the ordering of the "models" that articulate the pitch material to the moment of performance itself, rather than carefully rehearse a pre-planned version, may have had something to do with the less spiritual, but also valuably less pretentious atmosphere. Yet such bravado also produced some distracting showmanship and fussy business. And, admirable though the vocal and dramatic skills of these experienced singers were, they began flat, as the electronic pitch drone soon exposed.

Even so, this interpretation drew me in, so that after an hour I found myself captivated by Nicole Tibbels's outbreak of knowing laughter, followed by Terry Edwards's declamation (in English) of the frankly ludicrous poem involving a torpedo. The silence that then ensued seemed oddly powerful, not merely embarrassing. Stimmung is a "sex-tete" as well as a devotional ritual, after all, and all the more stimulating - as well as bizarre - for that. This no-nonsense (or at least reduced-nonsense) version even dared one to question whether Stockhausen and Cardew were really quite as far apart as they usually seem.