Having voted Philip Glass's Music in 12 Parts my record of the 1980s in last December's ''Critics' Choice'', a few words of explanation are clearly long overdue. At the time there was space only to comment that its ''sheer high spirits and mesmeric allure [have] provided happier listening than anything else for a long while'', an opinion that remains valid: it is one of the sunniest, most jewelled pieces of music I know. But it is also a highly unconventional score, modular in structure and open to all kinds of re-orderings or selections, and it won my vote not only on grounds of its musical content but also because it works so well on record, allowing the listener to make all manner of manipulations. Without question CD is the carrier to choose if you possibly can. All that flicking over of LP sides is simply a distraction.
To experience Music in 12 Parts is to share in modes of listening unfamiliar to many Westerners but fundamental to other great cultures of the world. In 1966, five years before work on Music in 12 Parts began, Glass studied with Allah Rakha, Ravi Shankar's drummer, and the influence certainly shows. Counting is all. Literally that; count with your fingers. The building blocks of Glass's music are cells which rarely change radically during the course of movements (the 12 'Parts'), nor develop beyond strictly limited confines. Repetition fixes them in the memory, but it is variation that provides the long term interest. Patterns regularly transform, either in predictable ways or through random change. It's game-like music: Glass sets up expectations, then gleefully leaves us guessing whether they're to be fulfilled or not.
No other work by Glass—or at least, none other currently available in the catalogue—contains so varied and wide-ranging a compendium of styles and techniques. There are pieces with tiny cells, others with patterns of marvellously convoluted complexity. In Part 1 the first cell occupies a mere 5 beats, the second 6, then 7, 8, 8, 8, 6, but the rules of the game turn out to have all manner of hidden twists: metrical ambiguities lure the ear into focusing on mid-points of phrases, not those crucial starts and ends on which counting depends. In Part 10, severely restricted melodic shapes are organized in large, internally-repetitive cycles that demand sharp listening if the music's tight structure is to be perceived as anything other than random doodling. Some Parts are built on additive principles in which cells gradually swell up through the accretion of secondary elements. Others—and these to my mind make the knottiest and most absorbing listening of all—operate on two planes simultaneously, one layer transforming while the other remains fixed. The first section of Part 8, the masterpiece of the cycle, takes this process to its most advanced state.
One thing should be stressed. This is not music for passive hearing. By all means sit back and let the stream of coruscating figurations simply flow by, but do so at the risk of missing the heart of the matter. Music in 12 Parts is rich in intellectual challenge, and with careful listening, seldom do its inner workings refuse to make themselves plain.
Needless to say, the music is also wickedly virtuosic. Glass here makes his first serious use of the busy bass-lines that have since become such a hallmark of his style, and they fairly keep the left hands of his keyboard players in trim. For the other members of the Ensemble—flutes, saxophones, and a vocalizing soprano—fast, tortuously angular lines that contain no breathing space at all test technique to its absolute limits. So unyielding is the music that the slightest flaw stands out, but this studio performance achieves what must surely be beyond human stamina and powers of concentration in the concert-hall. It should be played loud, just as the Philip Glass Ensemble in concert seek to overwhelm the listener with sound. None of the Parts lasts for more than 21 minutes in this somewhat curtailed performance, and they can be played as free-standing pieces. But the ultimate experience, it seems to me, is to settle down to a long evening, losing oneself in the ramifications of this gloriously inventive labyrinth of sound.'