Voice tracking is the radio industry practice of creating and broadcasting pre-recorded short voice segments with the purpose of convincing listeners there is a live and/or local DJ when there isn't. Often this is also syndicated to other stations, possibly hundreds. One radio personality records station IDs, liners, short chit-chat and it's all inserted in the appropriate metro to create the illusion of live local radio. Imagine one DJ in a production room recording in a row "Hello Chillicothe"... (pause) "Hello Spearfish" ... (pause) "Hello Bangor." With the aid of automation, one very over-worked DJ can program the "live" content for hundreds of stations in just a few hours.
Most writers just peg the beginning to the 1970s and walk away. I see it as having five major components that date back quite a ways. I'll give you the bullet points now then explain the hellish chronology.
- Records replace live music
- Syndicated live programing (networks)
- Syndicated recorded programing.
- Automated pre-recorded programming
- Robot DJs
On January 4th 1923 the first simulcast occurred. A concert live on 660 WEAF-AM in New York City was carried on 1230 WNAC-AM in Boston. the connection between the two stations was not by STL, it was by telephone line, leased from Bell telephone. More here. It was still quite uncommon since radio networks were still a novel idea, but again it was cost-effective. NBC launched in 1926, MBS in 1929, ABC (via fission) in 1943... Growth followed, and national networks aired the same programming on their affiliates coast to coast. But remember, this programming was still at least live. But over time listeners gradually stopped expecting all radio programing to be local.
Syndicated pre-recorded programming was a bit more insidious. You could record a program and air it anytime you wanted, even multiple times on multiple stations concurrently. Early on this was accomplished with transcription discs. These were duplicated and mailed to individual stations. Abbott & Costello started in 1942, Jack Armstrong in 1940, The Lone Ranger started before before 1935, and Lights Out, Eddie Cantor, and Dick Tracey around then as well. Tarzan I can confirm started syndicated on discs in at least 1934 and there are probably some even earlier. This freed up programmers to run the content when they wanted. Local DJs just punched in live for news, station IDs, traffic and weather.. In WWII AFRN used transcriptions heavily, further popularizing the practice. It was a cost-effective way to get well produced programming. All that's changed since then it the delivery methods, now we use FTP and satellite feeds. It still felt live. So why not? it was cheaper...
Then came automation. Paul C. Schafer installed the first automation system at KGEE, Bakersfield, CA, in 1953. He diligently tested his system and as a result, the FCC amended their rules in 1957 to permit the remote control of all radio transmitters. With it, he was able to run a radio station with a staff of three. More here. It caught on slowly, but then in the early 1960s the beautiful music format caught-on. More here. This was a format based around pre-recorded blocks of music run off of tape. It may or may not have been what Jim Schulke intended, but his rigid control of playlists put automation hardware in places it had not been before. The same rationalization still worked, if it's cheaper...
here. For the first time, radio stations aired 24/7 without staff. But clear channel was raking it in, because it saved so much money...
What I'm saying is isn't that Robot DJs are coming, it's that they've already been here for 30 years. We saw earlier this year a virtual DJ host a couple hours on KRTU-HD2. It's not a huge difference conceptually from voice tracking, but if tech support turns out to be cheaper than live DJs there will undoubtedly be more of it. More here.