Definition of Eltro information rate changer
The Eltro information rate changer is an analog recording tool for changing pitch without changing speed and vice versa. Patents for the device date from the 1920s. The Eltro was the first machine capable of changing audio pitch (frequency) and speed (time) independently of each other.
The Eltro was developed in Germany by an engineer, Anton Marian Springer (1909–1964). It was an accessory to a reel-to-reel tape recorder. Recorders compatible with the Eltro were introduced in the 1940s. The Eltro was first publicly demonstrated in 1953. By the mid 1960s, it was in many recording studios.
The Eltro was often used to adjust the timing of radio commercials to fit them exactly to their time limits. Using the Eltro, a recording engineer could control the length of a commercial without changing the pitch or adding or removing silence. It could also be used for a variety of musical effects.
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Frequently asked questions
What is Eltro information rate changer?
The Eltro information rate changer is an analog recording tool for changing pitch without changing speed and vice versa. Patents for the device date from the 1920s.