Placido Domingo's bid for the Pavarotti kind of superstardom

Placido Domingo, whose voice has warmed hundreds of thousands of hearts, leans back in a chair in someone's office at Alfred Knopf Publishing and warms to his subject.

There is an intangible something missing, he says, at the Metropolitan Opera in New York - ''this tremendous monster . . . I love more than any other theater in the world.'' He wishes the Met would foster ''a little warmer atmosphere''; the house has become ''too much of an institution, too big, too cold.''

But then, ''that is New York.'' And it is America, too; ''a very young country . . . a powerful country, a business country . . . superdeveloped in power. So, obviously, you have to have the best of the world in every respect. But not all the best of the world is always bought with power or money.

''It has to be care. You have to care about the people involved.''

Placido Domingo has written an autobiographical account of his life so far (''My First Forty Years.'' New York: Alfred A. Knopf, $15.95) that shows an ambitious nature as well as occasional pique and anger. But no one who reads it could accuse him of not caring about the feelings of the people involved in his career.

In fact, the book has been criticized for being too ''nice,'' for casting bouquets at almost everyone's feet. ''If I don't have anything good to say about somebody, I don't say it,'' he says.

And he means it. Almost.

Herbert von Karajan, the ubiquitously powerful German conductor, is a person about whom Domingo has little good to say. He complains that Karajan ''treated me capriciously,'' that he wanted Domingo to jump and change a contract commitment so that Domingo could sing with him. ''Many people have rearranged their careers for him like that,'' Domingo observes, ''but I am not accustomed to breaking my commitments.''

Under the placid geniality an occasional storm quietly brews, and you see Placido Domingo's ire. But not very noticeably. And, to his credit, he appears to be a man who does everything to bring a gentlemanly decorum and a meticulous politeness to his personal exchanges.

The Spanish tenor, who was raised in Mexico and built his career around the world, is wearing a blue pin-stripe suit and a gold chronometer watch. His olive complexion and long-curl dark hair, his darkly limpid eyes, all make him a strikingly handsome man. He speaks softly, as though carefully cradling his voice.

Along with his darkly handsome good looks, the warm glow of Domingo's voice, his musicianly instincts and training, and his positively athletic globe-trotting have launched the Spaniard into an orbit of his own.

Domingo is making a well-documented bid for the kind of superstardom attained by Pavarotti. Hence this book, as well as a recording with country-and-pop singer John Denver and numerous talk-show appearances. One obstacle along his path is that although Domingo's gifts run deeper than Pavarotti's, they are less ''media-genic.''

Pavarotti's voice is much lighter and, until recently, roamed more freely through the higher vocal range. He is a singer, pure and simple.

Domingo is a musician. He can conduct, and does: this year, ''Die Fledermaus'' at Covent Garden; next year, ''La Boheme'' at the Met. And he tackles roles with a musician's instinct.

Looking out the window, he speaks about ''the feeling of working phrase after phrase'' through the music as he sits at the piano, which is how he has taught himself role after role. ''First, almost passing by, and then going deeper and deeper into the part, and seeing why the composer wrote in that moment in that way. Why that phrase is going up, rather than going down. Why this sound is a quarter and this one is an octave.''

To sing as often as possible in all of the best possible places, he subjects himself, his voice, and his family to a daunting travel schedule.

Critics charge that Domingo is squandering his voice. Singers and their coaches and producers worry about the damage done by excessive singing coupled with rigorous traveling.

Not Domingo. With a sort of macho bravura (he once dreamed of being a bullfighter and has compared the fear and ex

posed life of the opera stage to that of the corrida), he has promised nay-sayers that he will sing his 25th anniversary performance at the Met.

''On the 28th of September, 1993,'' he says, ''I would like to sing the prologue of ''(The Tales of) Hoffmann,'' the first act of ''La Boheme,'' the second act of ''Otello,'' and the third act of ''Aida.''

Already, some critics claim, Domingo has trouble negotiating the higher registers of some roles. They complain of a thinness and rasping in his voice.

But the jury is still out on the question. ''It was about 15 years ago,'' wrote Harold C. Schonberg of the New York Times, ''that this writer predicted a short career for the gifted Spanish tenor. He was singing too much, in roles too demanding for his voice, and the intelligent conclusion was that he would be sung out in a few years. Mr. Domingo triumphantly proved that conclusion wrong. He went on to where he is today - the best tenor in action.''

''The best tenor in action'' has much to say, in his book and in person, about the musical world that he has made his own.

His book talks about Carlo Maria Giulini's ''combination of gentleness and intensity''; about Carlos Kleiber, whom he calls ''the greatest conductor of our day,'' marveling at ''the independence of his right and left arms, the subtlety of his subdividing, his way of anticipating beats that he knows tend to drag and of delaying others that tend to come too soon''; about Lorin Maazel - ''Maazel is not a cold human being, so I assume there must be a deliberate decision on his part to stay in a cool frame of mind.''

There is nothing cool about Placido Domingo. If anything sets his singing apart from - and above - Pavarotti, it is the con alma (literally, with soul) quality that seems to warm each note from within. Domingo loves to sing; and he loves to sing with great warmth.