Hollywood Sapphire Group 2002
January 2003 Meeting Presented by Ron Streicher
EARLY
DEVELOPMENTS IN STEREOPHONIC RECORDING
ALAN BLUMLEIN and WESTERN ELECTRIC
In
1931, Alan Blumlein was at work in his lab at Electrical Musical Industries
(EMI) in London on methods for improving the art of phonograph recordings.
The result of his work was published in his landmark 1933 patent in which he
describes a wide array of techniques for stereophonic recording and
reproduction, all of which are still in use today: the process by which
the human auditory system can perceive accurate spatial localization from two
loudspeakers; several basic stereo microphone pickup techniques, including
the Mid/Side technique and the crossed-figure-of-eight array which bears his
name; methods for creating and playing a stereophonic phonograph record,
including the 45/45 cutting system later developed and marketed by Western
Electric in the US; and stereophonic sound systems for motion pictures.
Around the same time, in 1931-2, Bell Laboratories
conducted a series of experimental stereophonic recordings with the Philadelphia
Orchestra conducted by Leopold Stokowski. On April 27, 1933, Bell Labs
“transmitted” a live performance by the Orchestra at the Academy of Science
in Philadelphia to an audience in Constitution Hall in Washington D.C. “that
effectively created the illusion of the orchestra’s presence behind the stage
curtain.”
These experiments served as the groundwork for the Bell
Labs “Symposium on Auditory Perspective” in 1934. Originally published
by the AIEE (now IEEE) in 1934, the full text of these Symposium papers has
recently been published on the website of the Audio Engineering Society
Historical Committee. Included are papers by Fletcher, Steinberg, Snow,
and Wente, among others, that discuss not only these classic recording and
broadcast experiments but the technology that made them — and all subsequent
developments in stereophonic sound in the US — possible. If you want to
download the Symposium papers, they are available from the AESHC Website as a
4.5 MB pdf file:
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