The “Telephone Enquiry Service” — Birth of the IVR
In the 1960’s, IBM sold the IBM 7770 Audio Response Unit for use by phone companies and call centers. The cutting edge system provided “audio responses to inquiries made from telephones.” The system created audio responses that were “composed from a vocabulary prerecorded on a magnetic drum.” A picture of the brochure for this revolutionary system is shown above. Audio responses were recorded and stored on the magnetic drum, and then the Audio Response Unit was programmed to listen for dial tone signals to determine which response to play. While today we are used to being able to configure IVR systems with different timeouts, the IBM 7770 system was hardcoded and an “inquiry is said to be completed when no further data are received for five consecutive seconds.”
The Introduction of Early Automated Speech Systems
Still in the 1960’s, IBM followed the 7770 with an updated system, the IBM 7772 which used “vocoder techniques” to generate several thousand distinct words in multiple languages. Similar units were produced by RCA (the “Cognitronic’s Speechmaker for use with Spectra systems) as well as Burroughs, Westinghouse Electric and the Rome Air Development Center. These early machines are the ancestors of today’s highly sophisticated text to speech, ASML and natural language processing systems. These systems were quite complex and required a significant amount of hardware. A sample of a Western Electric Company spec sheet for an “Automatic Number announcer and Verification Unit” in 1975 can be viewed here. The system used a Speechmaker Model 630 as the audio playback unit.
Each of these developments were intended to satisfy a growing market for “voice answerback systems”. Early applications were developed for the New York Stock Exchange, physicians, and students as well as for use in general telephone applications for inquiry and voice answers.