On Nov. 4, 1981, a few friends of George London gathered at the Kennedy Center to pay tribute to the great bass-baritone, who has been seriously ill since 1977, and to raise funds for his medical expenses.

It may have been the greatest array of operatic talent ever assembled on a single stage: not only such singers as Nicolai Gedda, Joan Sutherland, Marilyn Horne, James King, James McCracken, Tatiana Troyanos, Shirley Verrett, Justino Diaz and Ruth Welting, but also conductors Julius Rudel and Mstislav Rostropovich, who played piano accompaniment on this occasion, and singer turned impresario Beverly Sills, who was the ideal hostess.

Last November, with intermission and other delays, the performance took well over three hours. For tonight's telecast (Channel 26, 8 p.m.; stereo simulcast on WETA-FM), it has been neatly boiled down to two hours with very little musical loss and at least one significant addition. In the television edition, as the final credits are rolling up the screen, the recorded voice of George London is heard singing Schubert's "An die Musik": "Du holder Kunst, ich danke dir" ("Thou holy art, I thank thee"), a substitute for London's recording of "This nearly was mine" from "South Pacific," which opened the live performance. It was a very appropriate conclusion to an evening dedicated to musical friendship and to the art of song at its highest levels.

In a sense, an evening of superstars performing top operatic hits may be like a meal made up entirely of desserts, but in this case the performances were so fine, the repertoire chosen with such loving care, that few opera-lovers will complain of surfeit. The evening was not uniformly successful, of course, and for television some performances have been edited out--with the permission or even at the insistence of the singers. Musically, there is only one noticeable loss. Richard Stilwell sang all three of Ravel's "Don Quixote" songs, but only two are in the television edition. The young Washington singer seemed completely at home among the international superstars.

On television, some numbers come across with more impact than they did at the actual event--notably Horne's performance of "Ah quel giorno" from Rossini's "Semiramide" and Verrett's "Pace, pace" from "La Forza del Destino." It may be that memory fades these numbers because they came immediately before and after Gedda's performance of Lensky's Aria from "Eugene Onegin" (with Rostropovich at the keyboard), which was probably the highlight of the evening, if it had a single highlight.

Close-up camera work definitely improves the impact of Mozart's "La ci darem" as sung by the husband-and-wife team of Evelyn Lear and Thomas Stewart. It was the only duet on the program and the only number that offered real scope for acting, and Lear and Stewart took full advantage of the opportunity with results that bring the screen vividly to life. In contrast, Joan Sutherland's "Oh beau pays," which excited wild enthusiasm in the Concert Hall, shows small defects under the microscopic attention of video camera and microphones.

But most of the evening comes across as remembered from the live experience, and the high points of the program remain high points. Besides Gedda's and Stilwell's performances, they include James King singing the "Prayer" from Wagner's "Rienzi," McCracken singing "Nessun dorma" from Puccini's "Turandot," Carol Neblett singing "L'altra notte" from Boito's "Mefistofele," and other arias sung by Ruth Welting, Rockwell Blake, Tatiana Troyanos and Justino Diaz.

Besides being a tribute to a great singer, this evening showed the camaraderie and professional respect that great singers can have for one another. It was a superb antidote to stories of conflict and temperament that are not untrue but less than the whole truth. Ultimately, it is impossible to pick favorites in an evening whose least pleasant moments (probably the flattened high notes of Leonie Rysanek in "Dich teure Halle") are still endearing in their faded glory.