Philip Glass has become the third composer to sign an exclusive contract with the CBS Masterworks label. The first was Igor Stravinsky. The second was Aaron Copland. Admirers of Glass's music can rest assured he is traveling in distinguished company.
As the first fruit of the new arrangement, CBS has just released ''Glassworks ,'' an album of new pieces performed by the Philip Glass Ensemble and a few guests. To launch it, Glass and company have embarked on a nationwide concert tour, ranging from New York and Baltimore to Kansas City and Seattle, ending in Los Angeles on March 9 and a final performance in Rhode Island on March 26.
Arranged as a suite in six sections, the new ''Glassworks'' is remarkably accessible music, by contrast with the radical and innovative pieces Glass is best known for. As such, it may prove a breakthrough for him, bringing his pulsing, repetitive, cyclical style to a wider audience than ever before. This said, it's too bad ''Glassworks'' does not represent the composer or his style at their very best. It is accessible, all right, but parts of it are also rather tame. And while it contains passages of stunning lyric beauty, other portions are too busy or even cluttered.
After repeated hearings, it's clear that the best moments in ''Glassworks'' - and there are plenty of them - are logical extensions of the composer's recent movement toward conventional performance practice.
No longer does Glass write almost exclusively for an ensemble of heavily amplified woodwinds and keyboards: Just as his latest opera (''Satyagraha'') called for a medium-size orchestra, though without brass or percussion, the new suite incorporates French horns and strings, along with the usual saxophones and organs. The gentle textures of the ''Islands'' section are breathtakingly delicate, as are the flowing sounds of the later ''Facades,'' which contains some of Glass's most successfully sustained solo writing since the long soprano part near the end of his masterpiece, ''Einstein on the Beach.'' At such moments , ''Glassworks'' is a dazzling celebration of Glass's most ethereal instincts.
Other parts of the suite, however, would benefit from a dose of Glass's former assertiveness. The piano settings for the ''Opening'' and ''Closing'' sections seem a bit pallid, while the brass punctuations of ''Floe'' and ''Rubric'' are just a little too heavy for the swirling reed and synthesizer sounds that surround them. Among the up-tempo portions, only parts of ''Rubric'' seem precisely balanced - especially the delightful riff that recalls a Bernard Herrmann movie score. The other passages, engaging as they are in many ways, don't quite mesh the way Glass evidently wants them to.
Considered as a holding action rather than a step forward, ''Glassworks'' may be a clever move by the composer, who is probably wise to consolidate his growing popularity - and allay fears of errant avant-gardism - before proceeding to further experiments in a radical vein. From all indications, his soon-to-be-released film score will serve the same purpose, and sound very similar to his new disc. Moreover, there's no question that ''Glassworks'' grows on even the skeptical listener with repeated listenings, and in concert (played by the Glass ensemble, with synthesizers replacing the brass and strings) excerpts from it stand up well in the company of selections from the extraordinary ''Einstein on the Beach'' and ''Dance.''
As the recent triumph of ''Satyagraha'' proved, Glass is at the forefront of today's ''new music,'' with a rapidly expanding audience that includes not only other musicians, but large numbers of just plain fans who obviously relish his unique merger of rocklike pulse, jazzlike instrumentation, and classical complexity. If the new ''Glassworks'' recruits more such admirers, it could pave the way for further unexpected developments in Glass's unpredictable career.