The Metropolitan Opera's Centennial season opened dramatically with a major revival of its 1973 production of Berlioz's sprawling mythological drama ''Les Troyens.''
But what set the evening blazingly apart was the debut of the celebrated concert artist Jessye Norman as Cassandra - the first really important debut since the new house opened in 1966.
This opening night also reflected another important trend at the Met: a perceptible shift from financial insecurity to financial solidity. There was an evident feeling of self-satisfaction at getting a show on the stage without major mishap - and of selling out the house. Somehow Berlioz, in a very tangible sense, was only secondarily attended to.
The centennial of America's historically most important opera company reflects more the accomplishments of artistic director James Levine's ongoing tenure than any overview of the operatic contributions made by the company to the world of opera. Gounod's ''Faust'' opened the company's first night in 1883. The opening night here is this lavish opera by Berlioz, because Mr. Levine admits to not liking ''Faust'' and wanting to start a new tradition.
This season, no operas given their world premieres with this company - Puccini's ''La Fanciulla del West'' (1910) and ''Il Trittico'' (1918) being the most notable examples - are represented. Several of the operas introduced to the company during the Levine years will be offered, but not Alban Berg's ''Lulu ,'' which was surely Levine's most important contribution to the repertoire. Instead, we get the artistic and box-office fiasco production of Weill's ''Rise and Fall of the City of Mahagonny'' yet again.
It is the easiest thing in the world to sit in an armchair and tell the Met how it could do better in matters of casting, productions, and choice of repertoire. I will try to resist doing so. Nevertheless, certain strengths and weaknesses have been falling into predictable patterns over the past few years.
Maestro Levine has brought the level of the orchestra up to the highest of standards, and the playing in ''Troyens'' was magnificent except in a few instances made all the more noticeable in the general excellence. Mr. Levine, not always the subtlest of Berlioz conductors, found a new palette of colors in his approach, and quite often the rich mood-painting and ironic interjections rang out with startling impact. The chorus is in splendid condition, too. The core of any great opera house is its orchestra, chorus, and its roster of singers. The Met boasts a long list of names, ever growing.
Miss Norman got the evening off to a formidable start. The voice - one the great instruments of this or any age - encompasses an unusual variety of timbres , of volumes, of edges, from an open theater-filling fullness to a ravishing calm quietude. There were moments when the central strength of the voice seemed to wane as she negotiated the often-awkward Berlioz vocal line, but generally a fiery nobility marked her every vocal utterance.
Her blazing stage presence is marked by a striking economy of gesture, a pliant and magnificently expressive face, and a brilliant array of vocal colors (and crys-talline French diction) which she used to bring the role of the doomed Trojan prophetess to life. Her debut on this stage was long overdue.
But once Troy was sacked and Cassandra took her life, the performance assumed an aura of getting through without mishap. Overall casting was a series of compromises, as is increasingly the case at this house and in the opera world in general. Tatiana Troyanos's mezzo soprano is, in truth, somewhat undernourished for so big (and so long) a part as Queen Dido, yet she avoided the potential problems with shrewdness and flair. She proved particularly commanding in her last scenes, but the entire performance was unexpectedly distinguished from an artist who recently has not been at her best.
Placido Domingo is at his least effective in truly heroic roles. Aeneas demands a full-fledged heroic voice, especially in so large a house. There had been much speculation as to whether or not Mr. Domingo would sing at all, for he had gone on record as being unhappy with the part. Despite his efforts, only rarely - such as in the haunting love duet for Aeneas and Didon - did he deliver that blend of vocal beauty and characterizational acumen that mark his best work.
Secondary casting is more uneven than it should be. I could cite Paul Plishka's noble Narbal - lavish casting of an important singer in a lesser role but just as it should be in a distinguished house. The same could be said for Allan Monk's imposing Coroebus. On the other hand, there were tenor Philip Creech's hollow rendering of Hylas's haunting ballad, Douglas Ahlstedt's strident Iopas, and Jocelyne Taillon's mettallic-toned Anna, showing that all is not as it should be.
One would expect that this most ambitious of spectacle operas would be given a truly spectacular production. The stage is large enough, the machinery sophisticated enough to execute it. But the production as originally seen was clumsy, unattractive, and physically unsuited to telling so varied and involved a story. Now, as harshly lit by Gil Wechsler, the sets look most like part of a badly dated production of Wagner's ''Ring'': the space fights any potential for creating grand spectacle. That space also fights the ballets. Here Gray Veredon's contributions as choreographer were found consistently wanting. Director Fabrizio Melano, in fact, has treated the opera as a sacred oratorio: It moves like a concert in costume, with an almost willful disregard of Berlioz's specific stage instructions designed to let an important story be told.
What does this all say about the Met as it embarks on its second century of artistic life? Somewhere along the line all the concern for and justified pride in achieving financial security (a $100 million endowment drive should be completed by May of next year) seems to be detracting from matters on stage. There is still no sense of any one person looking at things such as lighting, directorial concept, and casting and saying, ''This will not do.'' Rather, it is a feeling of ''let's make the best of what we're committed to.''
The Met runs an impossible schedule of seven performances a week from September to June (including the tour). It cannot hope to offer great opera every night, particularly now in this voice-starved age. But it should be guaranteeing that the level of production not slip below competence and that the level of casting - primary and secondary - always reflect the best possible use of the singers on hand.
This is the company's responsibility as the most prominent purveyor of opera in the land. This should be its mandate during any year, particularly now when so many severe problems threaten the very life of the art form itself.