Stereophonic Reproduction from Film

Harvey Fletcher

On April 9 and 10, 1940, demonstrations of the stereophonic reproduction of music and speech, described in the accompanying article, were given at Carnegie Hall, New York, N. Y. This represented the latest development in a series of researches by Bell Telephone Laboratories, the first step of which was demonstrated in 1933 when a symphony concert, produced in Philadelphia, was transmitted over telephone wires to Washington, and there reproduced stereophonically and with enhancement before the National Academy of Sciences. — For the present demonstration, original recordings of orchestra, choir, and drama were made at Philadelphia and Salt Lake City; and at a later audition the artist or director was able to vary the recorded volume and to change the tonal color of the music to suit his taste. At will, he could soften it to the faintest pianissimo or amplify it to a volume ten times that of any orchestra without altering its tone quality, or he might augment or reduce the high or low pitches independently. The music or drama so enhanced is then re-recorded on film, with the result that upon reproduction, a musical interpretation is possible that would be beyond the power of an original orchestra, speaker, or singer to produce.

Print ISSN
Published
1940-06
Content type
Original Research
DOI
10.5594/J10083