Electrical transcriptions

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Electrical transcriptions were made practical by the development of electrical recording, which superseded Thomas Edison's original purely mechanical recording method in the mid-1920s. Marsh Laboratories in Chicago began issuing electrical recordings on its obscure Autograph label in 1924, but it was Western Electric's superior technology, adopted by the leading labels Victor and Columbia in 1925, that launched the new microphone-based method into general use in the recording industry.

Freeman Gosden and Charles Correll are credited with being the first to produce electrical transcriptions. In 1928, they began distributing their Amos 'n' Andy program to stations other than their home station, WMAQ in Chicago, by using 12-inch 78 RPM discs that provided two five-minute segments with a commercial break between.

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 By the end of the decade, the use of old phonograph music had largely been replaced by the new electrical transcription ...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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