Birotron

The Birotron (pronounced by-ro-tron) is a tape replay keyboard conceived by American musician and inventor Dave Biro of Yalesville, Connecticut, US, and funded by English keyboardist Rick Wakeman, Campbell Soup Company-Pepperidge Farm Foods in the 1970s.

A Mellotron-like instrument in the prototype stage and intended for mass production, it was featured on several albums and tours. It appeared in advertisements and received press in several newspapers as the next "latest and greatest" keyboard instrument. It also received over 1,000 advance orders from many prominent musicians worldwide, including members of the Beatles and Led Zeppelin.

Despite this success, it is now generally considered the world's rarest keyboard instrument in the genres of pop/rock music. It also retains the highest selling price for any Mellotron related keyboard, and since its inception, has been one of the most difficult to find, seldom seen, and least recorded instruments in the entire world.

The Birotron is a keyboard instrument that uses 8-track cartridge tapes to play sounds whenever a key is pressed on the keyboard. It is similar in concept to the Chamberlin and Mellotron, and was a forerunner of digital sampling. Keyboards like the Mellotron, Chamberlin, and Birotron were mainly used for strings, choirs, brass, and flutes, sounds not easily reproduced on the synthesizers of that era.

The major innovation of the Birotron is that it stores its sounds using 8-track tape loops, which allows it to play the sounds indefinitely, a great improvement from the 8-second limit of the Mellotron and Chamberlin. This also allows for dynamic and gradual changes in sound tones over time. A 10-minute tape loop could start off as a violin sound and gradually thicken into a viola or cello. A single repeating drum sound could gradually morph into several drum tones. Sound effects could change over time from the sounds of a stream to birds chirping. Sound collages could be made by combining tapes of various flutes, cellos, choirs, sound effects etc. This use of tape loops from 8-track cartridges also allows a Birotron owner to record his own tapes, and have a series of multiple instruments across the keyboard in the register they wished.

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Wikipedia