There is more than the usual amount of news in New York City's musical scene this fall, just at the time that the city's big newspapers are involved in one of their most persistent strikes. The musical directorship of the Philharmonic was taken over last Thursday by Zubin Mehta, signaling a dramatic shift from the repertoire and conducting style of his predecessor, Pierre Boulez.

Tomorrow night the Metropolitan Opera opens its 94th season with the leading tenor for the first night opening "Tannhauser" suddenly canceling all 28 of his engagements at the Met for the whole season, and a major Met premiere, "Billy Budd" by Benjamin Britten, coming up the second night.

The disgruntled tenor is James McCracken who was scheduled to sing 14 Tannhausers, 8 Don Joses in "Carmen" and 7 Radames in "Aida." The thing that is sticking in McCracken's throat (a very bad thing for any singer) is his strong feeling that he and not Jon Vickers should be singing in the "Otello" to be televised live from the Met on Sept. 25. Even though both his Jose and Radames dates are Saturday matinees, and therefore to be broadcast across the country, McCracken points out that the current production of "Otello" was designed for him and that the title role is one of his greatest. He is probably further irritated by the fact that Vickers is also slated to sing in the second televised opera, "The Bartered Bride," on Nov. 21.

However, the Met has survived fires, changes of management and cancellation of contracts by other singers; and it will carry on, if necessary, without McCracken. His title role in "Tannhauser" will be sung in the first four performances by Richard Cassilly, and in three more this fall by Jess Thomas. By next spring when seven more are due, McCracken might be back in the fold - stranger things have happened.

For those with a mathematical turn of mind, it will be of interest to note that the new season opening tomorrow night is the company's 94th, although the house opened in 1883. The reason for the discrepancy is that there was a fire in 1892 that kept the place dark for a season, and in 1896, the death of Henry Abbey, one of the company's co-directors, kept the Met from performing at all in the season 1897-98.

The most important new production at the Metropolitan this season, and its only premiere, is of the opera Britten wrote on Herman Melville's famous story, "Billy Budd." From the time of its world premiere at Covent Garden in 1951, Britten's fourth major opera has enjoyed a special kind of approval. Following his first powerful opera, "Peter Grimes," which the Met has given frequently in superb productions, and the two succeeding operas, "The Rape of Lucretia" and "Albert Herring." Britten's "Billy Budd" occupies an almost unique position in opera: It has an all-male cast.

Melville's drama, as is so often the case in his writing, operates on several levels. Its action is set in motion on board the Indomitable during the naval wars waged between France and England in the final years of the 18th century. English naval officers' nerves are tense because of recent mutinies.

But it is not the flogging of seamen or their conduct under the fire against a French man-of-war that is at the heart of Melville's novel. It is about the eternal struggle between good and evil - represented by the characters of Billy Budd and John Claggart, the Indomitable's master-at-arms - as the ship's captain, Edward Fairfax Vere, called "Starry Vere" by his men, is faced with the inescapable decision to hang Billy for having murdered Claggart.

The Metropolitan has cast the opera strongly: Peter Pears, at the age of 68, will sing the role of Vere, which he created in the Covent Garden premiere. The title role will be sung by baritone Richard Stilwell, whose residence is in Fairfax, Va., and who is now a leading baritone with both the Metropolitan and the New York City Opera.

No singer today knows more about Britten's music than his lifelong friend and artistic collaborator, Pears. In spite of the fact that his debut took place over 40 years ago, Pears has kept his voice in prime condition. Four years ago when he sang in the Met's first production of Britten's "Death in Venice," he was heard easily throughout the huge house, and his enunciation was so flawless that every syllable he sang could be understood. An important debut will take place at Tuesday night's "Budd," when the English conductor Raymond Leppard makes his first Met appearance.

The new season will be one of the longest in Met history, a total of 30 weeks during which 24 operas will be given for a total of around 210 performances. In addition to "Billy Budd," four other operas will enjoy new productions this year.

They are Verdi's "Don Carlo," Donizetti's "Don Pasquale," Wagner's "Flying Dutchman" and a greatly anticipated revival of "The Bartered Bride" by Smetana. The latter will enjoy the most luxuriant casting, with Jon Vickers and Nicolai Gedda in its major tenor roles, sporano Teresa Stratas and the giant Finnish bass, Martti Talvela. Among the world's great conductors, Karl Boehm is returning this season to lead Beethoven's "Fidelio."

There will be Metropolitan debuts of American sopranos Arleen Auger and Carol Neblett, Soviet artists Markvala Kashrashvili and Yuri Mazurok, and the Swedish baritone, Hakan Hagegard, who starred in the role of Papageno in the recent triumphant film version of Mozart's "Magic Flute."

The Metropolitan's music director James Levine, continues to assign himself such plums as the opening night plus "Otello" and "The Bartered Bride." He will hsare the podium with a dozen others including Boehm, Leppard, Erich Leinsdorf, Peter Maag and Michel Plasson. The last will have one of the top assignments of the season when he conducts Poulenc's "Dialogues of the Carmelites," which was first introduced to the Metropolitan two seasons ago.

In addition to the telecasts of "Otello" and "Bartered Bride," the Met will be seen as well as heard on Dec. 19 in Puccini's. "Tosca" and, later in the winter-on a date still to be announced in Verdi's "Luisa Miller." Its regular Saturday afternoon broadcasts will begin on Dec. 2 with "The Bartered Bride."