Arts and entertainment reports from The Times, national and international news services and the nation’s press.

DANCE

The Milli Vanilli of Dance?: The producers of “Riverdance” have revealed that the sound of the hit production’s tap-dancing is prerecorded for live shows. Executive producer Julian Erskine told London’s Times that the tap sounds are taped in advance to “give the audience the best possible product.” He also told British radio stations that audiences have become so demanding they expect perfect performances every night, even in large arenas where the dancing sounds fail to reach the back seats. So while those in the first few rows may actually hear the steps live, everyone else gets the Memorex version. “Riverdance” has become so successful that there are now eight international touring troupes.

TELEVISION

‘Magic’ Act: Magic Johnson’s new late-night talk show “The Magic Hour” premiered with reasonably good ratings Monday night, averaging 8% of the available audience in 40 major cities monitored by Nielsen Media Research. Those results represent a 20% increase over results for the same stations during May. The program delivered one of its highest ratings locally on KTTV-TV Channel 11, drawing more than 260,000 homes in the Los Angeles area, ranking fourth in its 11 p.m. time slot. “The Jerry Springer Show”--with 350,000 homes tuning in to KCAL-TV Channel 9--ranked No. 1 in the period.

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Competition Out of the Way: “Vibe,” one of two syndicated late-night talk shows that premiered last August but failed to attract large audiences, has been given the ax. The timing of the announcement from “Vibe” distributors Columbia TriStar Television coincided with the strong debut of “The Magic Hour,” which comes from rival syndicator Twentieth Television. Columbia honchos said that “Vibe,” hosted by Sinbad, has not gained enough viewers to “sustain the necessary investment.” The show--seen locally on KCOP-TV Channel 13 at 11:30 p.m.--will continue airing until Sept. 11 with new and repeat episodes. “The Keenen Ivory Wayans Show,” which premiered the same day as “Vibe,” had already been canceled.

STAGE

Final Tony Notes: The luck of the Irish brought not one but two utterances of the “F-word” to Sunday night’s Tony broadcast on CBS, an occurrence rarely found on network television. Irish actor Tom Murphy used the verboten expletive as he thanked playwright Martin McDonagh for writing a “great [expletive] story and great [expletive] lines” in “The Beauty Queen of Leenane,” for which he had just won best performance by a featured actor. Murphy--who was echoing his character’s repeated use of the word--pronounced the word as the Irish do--with an E as the second letter, and no G at the end. In an apparent case of cross-cultural misunderstanding, a CBS spokeswoman said a network censor heard the word, was not familiar with the pronunciation and “decided to give the benefit of the doubt on it because she didn’t want to disrupt the acceptance speech.” Hence CBS did not edit or bleep the words from either the live East Coast feed or the delayed West Coast broadcast. It is believed to be one of the few times the word, or even a close approximation, has found its way into a network broadcast, except for sports events at which microphones are placed on the sidelines near players. When comic Charlie Rocket used the expletive on NBC’s “Saturday Night Live” in 1981, for instance, he was soon out of a job. . . . Meanwhile, shows that came away empty-handed from Sunday’s awards have started to announce their closings, including the Jane Alexander drama “Honour” (closing June 14 after 57 performances) and “The Diary of Anne Frank” revival (now billed as in its “last weeks”). Business has apparently improved for Tony winners, however, including the above-mentioned Irish drama “The Beauty Queen of Leenane”--with a total of four awards--which did three times as much business Monday as it did a week ago, a play spokesman said.

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A Quick Divorce: Nicky Silver’s play at the Sledgehammer Theatre in San Diego is now called “My Marriage to Marisa Tomei” instead of its previous moniker, “My Marriage to Ernest Borgnine.” After Borgnine heard about the play from Daily Variety columnist Army Archerd, he threatened legal action, Archerd reported. “We could fight, but we hardly considered this to be a burning 1st Amendment issue,” Sledgehammer executive director Ethan Feerst told The Times. So Silver asked Tomei, described by Feerst as “a close personal friend” of Silver’s, if he could substitute her name in the title. The play includes one brief monologue about Borgnine’s ex-wife Ethel Merman, five sentences of which refer to their marriage; one sentence that lasts about six seconds has been replaced by a bleep tone to avert further legal threats, Feerst said. The play’s run, which was to have ended Sunday, has been extended another two weeks.

QUICK TAKES

NBC has reversed its ban on ads for the Norm Macdonald movie “Dirty Work,” having accepted a commercial scheduled to air tonight during the NBA playoffs. The network’s New York brass overruled the ban imposed by NBC West Coast President Don Ohlmeyer, who has feuded with Macdonald since the latter’s departure from “Saturday Night Live.” . . . Long Beach’s young Museum of Latin American Art has lost its second executive director after the resignation this week of Lee Scott Theisen. The museum cited “mutual differences” in announcing the departure. The initial director, Pat House, left in April 1997, five months after the institution’s opening. The museum will initiate a search for Theisen’s successor, with David Wood having been appointed museum manager. . . . More than 2,000 music industry executives will gather at the Century Plaza Hotel on Thursday for “R&R; Convention ‘98,” a three-day gathering sponsored by the trade publication Radio & Records. Scheduled speakers and performers include Garth Brooks, Paula Cole, Dick Clark, Casey Kasem, Chris Carter (“The X-Files”), Richard Branson (Virgin Records) and Edgar Bronfman Jr. (the Seagram Co.). . . . Citing her desire to do other projects, actress Gena Lee Nolin has opted not to return to the syndicated series “Baywatch” next season.