Whether or not it was a heavens-to-Betsy cultural event, NBC's "Live from Studio 8H" was certainly honest-to-goodness television. There hasn't been a live classical music concert in prime time on a network in about three decades, and this one came off beautifully.

Of course the ratings for the Wednesday night telecast were not high. After all, Verdi, Wagner and Ravel are poor commercial competition for Kelly, Kris and Tiffany -- "Charlie's Angels." Said coproducer Alvin Cooperman yesterday, "Everyone says they're not expecting good ratings, and they're not, but when the bad ratings do come in, it's going to be a downer anyway."

In fact, the ratings were worse than feared, according to Neilsen "overnights" from major cities. In New York, "Live" got a 10 percent share of the viewing audience, in Chicago 9 percent and in Los Angeles, 8 percent. oSingle-digit "shares" are as much an anathema to networks as triple-digit inflation would be to the nation.

And yet even with these low numbers NBC Research was willing to estimate optimistically, after some coaxing, that as many as 10 to 12 million Americans saw this sparkling and enthralling broadcast. That number of people would be sufficient to fill the Kennedy Center Concert Hall every night for about 13 years.

In addition, the Wednesday night concert by Zubin Mehta and the New York Philharmonic did considerably better than Mehta's last outing with the orchestra on public TV's "Great Performances" series on Nov. 14. The New York share that night was 2.8, Chicago 2.8 and Los Angeles 1.7.

The triumph of the broadcast was that director Rodney Greenberg was able to make 90 minutes of music intensely and enjoyably visual. Studio 8H was once the home of Arturo Toscanini and the now-disbanded Nbc Symphony, and the concert was staged as a tribute to him. NBC spent $400,000 to renovate the studio (home of "Saturday Night Live") and make it both accoustically sound and hospitable to the roamings of cameras.

With virtually no technical problems whatsoever, Greenberg made the music come alive on the home screen with strikingly composed close-ups of brass or strings and shots of the expressive Mehta -- far more demonstrative a ham than Toscanini ever was -- caught in bursts of bravado or elation. It was brilliantly, almost flawlessly, done.

"I'm waiting for Fred Silverman to pick up the phone and call me and tell me we can start to work on the next one," Cooperman said yesterday after a sleepless night. "Fred's been a man of his word on this thing, and I believe he'll do four a year."

At a party afterwards attended by all 240 of those in the studio audience -- including John Chancellor and NBC board chairman Jane Cahill Pfeiffer -- Silverman told one reporter the concerts would "definitely" continue, no matter what the ratings.

At the program's opening, announcer Martin Bookspan noted that Toscanini's radio and television concerts had "enriched the life of this country." This is something that cannot often be said of television. On Wednesday night, even if "only" 10 million people were watching, those 10 million people went to bed darned enriched.