Three faces - one hardly known, another familiar, the third very famous, but in an unfamiliar context - have been dominating the New York music scene these past few weeks.
The first is Myung-Whun Chung, pianist-brother of the celebrated violinist Kyung-Wha Chung, who decided several years ago to switch over to conducting and has been making an important name for himself. Second, there's Lorin Maazel, who abruptly resigned as head of the Vienna State Opera last spring and just as abruptly signed on as the Pittsburgh Symphony's music adviser for the next two years. That orchestra is searching to replace Andre Previn, who will now head the Los Angeles Philharmonic. Third is tenor Placido Domingo, who has been singing his first US Lohengrins at the Metropolitan Opera and just made his New York conducting debut in that company's spectacular Franco Zeffirelli production of Puccini's ''La Boheme.'' Myung-Whun Chung
Mr. Chung had started to make a name for himself as a pianist. (In fact, he recently recorded the Tchaikovsky Piano Concerto with Charles Dutoit for London Records.) But clearly a baton was more interesting to him. Shortly after he graduated from Juilliard, he became an Exxon conducting fellow, and through that program he got to work with Carlo Maria Giulini for several seasons in Los Angeles. His career has since taken off in a big way - symphonic and now also operatic. In Sweden, he has just begun a recorded cycle of the Carl Nielsen symphonies for BIS. The first release - the Second Symphony and the Aladdin Suite (BIS-LP-247) - reveals a conductor of great energy and style, interested in the long line - the musical undertow that keeps a movement and a symphony an entire musical entity.
These qualites he showed off in abundance recently in two programs at the New York Philharmonic. In the relatively obscure Dvorak Third Symphony, Chung made a convincing case for a work of some attractiveness as he explored the budding ideas that Dvorak would bring to full flower in his later works. Throughout, Chung got the Philharmonic to sound like an important orchestra (for a change!).
In the following program, Chung led a rich, melancholic, plangent performance of Prokofiev's thorny (and also rarely encountered) Sixth Symphony. It is perhaps the composer's deepest, most affecting symphony, and if one is willing to go with the composer as he jumps from episode to episode, he discovers a world of emotions that Prokofiev barely touched in the more facile and glib Fifth Symphony.
As an accompanist, Chung is also distinguished. He and Emanuel Ax gave a gorgeous account of the Chopin Second Piano Concerto - sumptuous, heartfelt, technically fluent, and interpretively bracing. Mr. Chung also partnered his violinist sister in the Dvorak Violin Concerto. She filled the hall with pliant tone and persuasive passion, while Chung saw to it that the orchestra - which seemed to be listening to and responding to the soloist - was in good sonic and emotional balance. Lorin Maazel
Mr. Maazel was having one of his arbitrary evenings with the Pittsburgh in Carnegie Hall. But it was evident just what a fine orchestra Previn had been developing.
The sounds made in the Barber ''School for Scandal'' overture rivaled that of many of the best orchestras of the day. The limpid sheen in the Prokofiev First Violin Concerto was balm to the ears.
In that concerto, Soviet violinist Victor Tretyakov made one of his tragically rare visits to these shores. One forgets, until he hears the Russian string players live, just what astounding instrumentalists they are. The size of the tone conjured from his fiddle, his patrician sense of line, the variety of timbres, all mesh together into something extraordinary - for which one will endure the occasional lack of tenderness or passion.
Passion was utterly missing from Maazel's reading of the Sibelius Second Symphony. From an orchestra that could give Maazel Sibelian blends 'til doomsday , he chose rather to demand angularities and harshness. Placido Domingo
Anyone who expected to hear a mere ''stunt'' when Placido Domingo conducted Puccini's ''La Boheme'' would have left the Met disappointed. The Met orchestra can play quite poorly even for guests it honors and likes, yet for Domingo it played like the opulent opera orchestra we now know it to be. But more to the point, this was an accomplished, traditional reading of Puccini's score, generally very fair to singers in terms of balance, and fair to Puccini in terms of articulation of orchestral detail. At a few odd moments, he seemed to bog down in some distracting details, and here and there a less-than-natural tempo switch gave his performers passing trouble.
How it is possible that the Met could have assembled such a pitiful cast of singers for the occasion is something else again. With the exception of Myra Merritt - a spirited Musetta who may be pushing her light voice too strenuously but makes a strong impression on stage - there was more to deplore than recommend. It was the sort of vocal evening a second-level European house might blush to put on. Both Mr. Domingo and the audience deserved better.