he was the telegenic "diva next door," a friendly redhead from Brooklyn whose friends called her Bubbles; she was an aggressive Manhattan snob who never let it be forgotten that she did hold grudges. She was the warmest and most brilliant American coloratura soprano of her time; she was a high-culture power broker and adept political infighter. Those who knew her slightly liked her enormously; those who knew her better were sometimes a little afraid of her.

Beverly Sills, who died of lung cancer yesterday at the age of 78, was a complicated person, and any attempt to sum up her life and work will necessarily turn into a string of contradictions. Over the course of her 70 years before the American public (she made her debut on radio at the age of 7, where she was heard singing in a commercial for Rinso laundry soap), Sills helped put the New York City Opera on the map, first as the biggest star of Manhattan's "second" opera company and later as its director and tireless spokeswoman. Still later, in 1994, she became the chairwoman of Lincoln Center for the Performing Arts and then, in 2002, chairwoman of the Metropolitan Opera, the august organization across Lincoln Center Plaza from City Opera that had denied her the chance to sing on its stage until well after her best years were behind her.

At the peak of her career, before the ultra-hyped Three Tenors swept everything before them, Sills was probably the best-known classical singer in the United States. When she retired from the stage after a gala farewell concert in October 1980, the program included appearances by everybody from Placido Domingo to Walter Cronkite to Carol Burnett, and the tickets went for more than $100 each, an extraordinary amount in those days.

Throughout the '70s, a Sills appearance in a single opera would sell City Opera subscriptions for a full season. "I'm really not being immodest; that's just a fact," she told me in 1987. "I was helping to keep the City Opera afloat long before fundraising became one of my principal duties." By that point, she had been with City Opera for 32 years, in one duty or another, and its director for eight years.

Sills's tenure at the helm of the City Opera, which lasted from 1979 to 1989, was not an easy one. She inherited grave financial troubles. She had to deal with a particularly angry strike by the City Opera orchestra in the summer of 1983 and with a 1985 warehouse fire that destroyed $10 million worth of costumes, sets and other material for 74 productions. And, along with her company, she suffered the loss of dozens of young City Opera employees to AIDS in the 1980s and early 1990s -- conductors, singers, designers, directors and others. No other New York arts organization was so hard hit.

But she had enormous triumphs there as well. Chief among these must be her decision to introduce English supertitles to the City Opera in 1983, which ended what had long seemed an inherent language barrier with one deft slice of the Gordian knot. The City Opera was the first major troupe to employ titles, which had long been dismissed within hidebound operatic circles as simultaneously unworkable and a shocking vulgarism, even if they could be implemented. It took the Met another dozen years to come up with its own system; today, opera is unthinkable without titles.

Sills wrote two autobiographies. "Bubbles: A Self-Portrait" was published in 1976 and became a minor collector's item due to the fact that the very first sentence in the book contained an embarrassing typo ("public" was rendered "pubic," changed in later editions). "Beverly," published in 1987, was much less guarded and contained a number of surprisingly personal attacks on critics, opera-house directors and fellow singers.

"I'm not Bubbles anymore," she told me in an interview when the book was published. "I've come to the stage in life where I'm not afraid to use my influence. I've gone above the heads of my directors, told my singers how to sing, even rearranged the lighting. Of course, we'll talk about it; I don't even mind getting into an argument. But if I don't prevail, I will prevail."

The record companies did not do well by Sills. Her great fame dated from the 1966 New York City Opera production of Handel's "Giulio Cesare," when the world suddenly awakened to the fact that there was a distinctly American diva in our midst, with a voice that was sweet, healthy and versatile, and a temperament that was suited to both daffy pyrotechnics and hefty dramatic roles.

Unfortunately, like many another so-called overnight success, Sills had then been working hard for quite some time -- 1966 was her 11th season with the City Opera, and there was radio before that -- and, during the years when her voice was at its freshest, she was invited to make only one recording, a complete performance of Douglas Moore and John Latouche's "The Ballad of Baby Doe" in 1959.

And so admirers were delighted in 2006 when Video Artists International discovered and released on DVD a telecast of Richard Strauss's "Ariadne auf Naxos" from January 1969. The late Erich Leinsdorf conducted the Boston Symphony Orchestra and there were winning performances from Claire Watson, John Reardon, Robert Nagy as Bacchus, and a very young Benita Valente.

But Sills absolutely stole the show, with the joyous, flighty celebration of unfettered hedonism that Strauss created for his character Zerbinetta. It is the coloratura aria to end all coloratura arias -- all trills, arpeggios and stratospheric leaps -- and it goes on forever. Still, when sung with Sills's radiant good humor and triumphant virtuosity, it calls to mind nothing so much as a Fourth of July sparkler that not only refuses to burn out but throws off ever brighter, bolder light as its time elapses.

For those who remember Sills mostly as a personality, through her decades as an arts administrator and her appearances on talk shows, let this remarkable "Ariadne" provide posterity with palpable evidence of what the excitement was all about.