Popular Radio, February, 1923, pages 120-123:

How  the  First  Great  Concert  to  Be  Broadcast  with  the  Help  of  Telegraph  Wires  Was  "Picked  Up"  in  One  State  and  Transmitted  to  Another  State  to  Be  Sent  Out  by  Radio
POPULAR RADIO sponsors another unique and successful experiment in broadcasting great programs to a great audience
microphone installation
amplifying apparatus
new vacuum tube
A SIGNIFICANT feature of the broadcasting of this season's concerts by the great City Symphony Orchestra of New York is the fact that they are being broadcast by the "pick-up" system without the use of telephone wires. And they are being broadcast with a clarity and a power and a quality of tone that marks them as perhaps the most successful symphony concerts ever sent out by radio.
    The refusal of the American Telephone & Telegraph Company to furnish the land wires and service for the purpose of broadcasting these concerts from the Westinghouse station WJZ left but two alternatives: either the project had to be abandoned (thereby depriving the radio fans of the East of what have proved to be the most popular symphonic programs ever broadcast) or else means had to be found for carrying out the plan without the telephone company.
    The success attained last fall in broadcasting from WJZ the side-line reports of the big football games at the Polo Grounds (a project sponsored by POPULAR RADIO with the aid of wires obtained from the Western Union Telegraph Company, naturally suggested the possibility of using the same methods for broadcasting the concerts. And with the helpful cooperation of the Western Union officials with the Westinghouse experts this plan has been carried into effect with results that have surpassed expectations.
    When POPULAR RADIO initiated last summer the project of broadcasting the concerts of the New York Philharmonic Orchestra through WJZ it created a demand for good music and established a precedent that has been met with increasing and encouraging emulation throughout the country. This experiment demonstrated a possibility of radio broadcasting which had not, up to that time, been generally realized. The interest aroused by the Philharmonic concerts spread over the entire United States and stimulated a demand for such classical music as comes within the popular range. It was meet such a demand that the City Symphony programs were planned, and it is especially fitting, therefore, that the range of its series of "popular concerts" should thus be indefinitely widened to include the largest possible audience--a place which is directly in line with the purpose of the patrons of the new orchestra.
    For the City Symphony Orchestra is new; indeed, it is the youngest of the three important organizations of its kind in New York. It was founded by the Musical Society of the City of New York to fill a definite and important need in the musical life of the city--that of bringing music, particularly orchestral music of he highest standard, within the reach of the general public. Its personnel consists of eighty--three players. To attain the object of its founders, only a modest admission fee is charged for its concerts, particularly so for the "Pop" concerts, which are being given at three o'clock on Sunday afternoons throughout the winter.
    The programs are composed of the gems of the lighter classics, together with short symphonic pieces. Such music, experience has shown, is the best fitted for the general music-loving radio public and meets with the widest approval. And on Sunday afternoon the air is comparatively quiet and people like to gather quietly and listen to good music.
    The first concert broadcast was given at the Manhattan Opera House on November 25th; the later concerts are being given at the New Century Theater. The series was inaugurated by a short talk prepared by the editor of POPULAR RADIO. How the mechanical problem of broadcasting a concert held in one State from a radio station located in another State by means of wires furnished by a telegraph company is an interesting story in itself.
    First of all, a special wire connecting with one of the regular wires to the Western Union's terminal station at Walker Street was strung to the microphones and the amplifier, located on the stage of the theater. The wire is equipped with a special type of protective device to keep outside interference down to a minimum. From Walker Street the re lay is made to WJZ in Newark on a special circuit which has been set aside for broadcasting--the circuit that was used for broadcasting the World Series of baseball games and the Polo Grounds football games. (Details concerning this special circuit were given in the January issue of POPULAR RADIO.) It is safe to say that the helpful experimental work of the Western Union on this circuit has played a considerable part in the splendid transmission of these notable concerts.
    At the theater itself are placed four microphones, one is located at the left of the stage in the wings for the operator of the switch box, who also serves as the announcer: a second microphone is placed at the right of the stage, hung about twenty-five feet high and facing the audience in order to catch the applause a third instrument is located at the outer edge of the orchestra pit for the soloists; and a fourth--the most important of all--is placed at the footlights in front of the orchestra.
    The placing of a microphone so that it will most effectively catch the multiplicity of sound that comes from an orchestra of eighty-three pieces, or for that matter a problem still in its infancy. As time goes on there undoubtedly will be rearrangement of the pieces in orchestras to more effectively bring the microphone the sound waves their true values. Another problem that has also just begun to be studied is the question of acoustics from a radio standpoint. It is possible that in the building of future concert halls and opera houses this problem will be given special consideration.
    The radio signals are amplified at the theater; at the Newark station they are further strengthened by other amplifiers. Here there is also a special filter circuit to improve the quality of sound before it is amplified.
    The story of these City Symphony concerts is not a story of long-distance broadcasting. It cannot be, as the daytime broadcasting radius does not extend much over two hundred miles. The development of long-distance broadcasting is one of the big problems before the radio world, but so, too, is the question of the kind and quality of broadcast entertainment, and, though these concerts reach out through a fairly broad radius, the important factor is that they constitute entertainment that can be classed as of permanent cultural value, broadcast over an area occupied by many millions of people--all of whom are at liberty to "plug in." Yet evidence of the widespread interest aroused has come in letters from points as far north as the city of Toronto in Canada, and as far south as Atlanta, Ga.
FOLLOWING the successful broadcasting of the concerts of the New York Philharmonic Symphony Orchestra last summer (a project initiated by POPULAR RADIO) the management requested this magazine to arrange also for the broadcasting of its series of nineteen Educational Concerts during the present season. Provisions for broadcasting them through the Westinghouse station WJZ were blocked, however, by the refusal of the American Telephone & Telegraph Company to furnish the necessary land wires or service. So much pressure was brought to bear from influential sources to carry the project into effect, however, that the telephone company arranged to broadcast about half of the concerts through its own station, WEAF.