Electrical transcription

Electrical transcriptions, "recordings made exclusively for radio broadcasting" were widely used in the era of old-time radio, They provided material—from station-identification jingles and commercials to full-length programs—for use by local stations.

Physically, electrical transcriptions look much like long-playing records that were popular for decades. They differ from consumer-oriented recordings, however, in that they were "distributed to radio stations for the purpose of broadcast, and not for sale to the public.... The ET had higher quality audio than was available on consumer records" largely because they had less surface noise than commercial recordings,

Electrical transcriptions were created in the mid-1920s. Sources differ as to exactly when (and by whom) their creation occurred. A reference guide to music technology says that Marsh Laboratories, in Chicago, Illinois, produced the first electrical recordings in 1924, using the Autograph label. Meanwhile, a biography of Leopold Stokowski cites Western Electric Company as developing American electrical recording in 1925.

Freeman Gosden and Charles Correll are credited with being the first people to use recordings (albeit an older form predating electrical transcriptions) to distribute their Amos 'n' Andy program to stations other than their home station, WMAQ in Chicago. They used 78 RPM discs to provide two five-minute segments with a commercial break.

One audio historian wrote: "New methods of electronic reproduction and improved record material that produced very little background noise were developed ... By the end of the decade, the use of old phonograph music had largely been replaced by the new electrical transcription ... With the fidelity available, it was difficult to tell a transcription from the original artist." A 1948 ad for a disc manufacturer touted the use of transcriptions on the Voice of America, saying, "A substantial part of these daily programs is recorded and, due to the excellent quality of these transcriptions, such recorded portions cannot be distinguished from the live transmissions."

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