San Francisco Chronicle, June 18, 1922, page F7:

Broadcasting  Service  of  1920  Compared  With  Concerts  Now

    The playing of large Shrine bands by radio from several broadcasting stations in this city last week recalled the broadcasting feats of the California Theater in 1920, when it opened in this city the first broadcasting service in regular schedule ever carried out.
    The radio set at the California Theater sent out daily the music of its own orchestra, playing in the course of the performances and interesting experiments were made in determining the best method of catching the music in the microphones and transferring it to the air.
    The seating of the orchestra, which is considerably changed from the usual arrangement for modern broadcasting, could not be altered in the theater, nor could the room be protected against echoes.
    Modern broadcasting rooms are hung with heavy drapes to absorb echoes, and large orchestras are seated so that the percussion instruments and loud horns are removed from the microphones. Such alterations were not practical in the California Theater, where the orchestra was playing for an audience within the building as well as one scattered throughout the state, and other means were tried to secure best results.
    The microphone horn was moved to various parts of the theater and tests were made to determine the best location. It was finally found, by a process of elimination, that a horn suspended forty feet above the heads of the players transmitted the sounds most effectively by radio. The horn had an unusually large opening for gathering in the sounds. When suspended over the string instruments, removed from directly above the drums and brasses, the effect was far better than when the horn hung above the center of the orchestra