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Birotron B90

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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.

Another improvement is a separate attack and decay envelope for each note (like a VCA on analogue synthesizers) that allowed each note on the keyboard to independently begin and sustain. Notes could come in instantly or gradually over time — swelling in volume over a minute. Notes could decay quickly or slowly fade out, or infinite sustain could be achieved – giving the illusion that the instrument is playing itself. A ten turn pitch knob allows the sounds to be vastly speeded up or slowed down. The drawback was that the actual attack of a note had been lost in this system, and the electronic attack and decay were essential to recreate it.

The attack, sustain, and 10 turn pitch features allow for effortless creation of ominous stacked sound swells and pitch bends reminiscent of Mike Pinder's Mellotron work on "Have You Heard" (1969), and Rick Wakeman's Mellotron work on "I Get Up, I Get Down" from Close to the Edge (1972). By varying the attack and decay controls while playing — sounds, notes, and chords could be stacked upon, blended, sustained, and then suddenly morphed by changing the 4 position track selector. The keyboard action also allows the user to play as fast as they want to, having a very light touch. This allowed the player to create both a dynamic sound, and do fast runs the way a symphony might actually play. This was not always easy to do with the Mellotron or Chamberlin. These combined features plus a lighter weight and small size attracted huge interest from most major musicians of that time.

Technical Specifications
Type: Analog
Synthesis: FDSP
Oscillators: 8
Envelopes: 1
Evelope Paramerters: Attack, Decay
LFO: 0
Polyphony & Tuning
Polyphony: 8
Timbrality: 1
Tuning: Standard
Modes: Polyphonic
Patches RAM: 1
Case: Desktop, Keyboard
Audio Output Connections: 1/4" Phone Jack, Mono Out
Audio Output Count: 1
Year Released: 1977
Year Discontinued: 1979
Units Made: 15
Used By
Klaus Schulze, Tangerine Dream, Rick Wakeman, Dave Biro
Design Notes:

The Birotron (pronounced By-ro-tron) is a tape replay keyboard conceived by Dave Biro of Yalesville, Connecticut, US, and funded by Rick Wakeman of the progressive-rock group Yes, and Campbell Soup Company-Pepperidge Farm Foods in the mid-late 1970s.

A Mellotron-like instrument in the prototype stage, and intended for mass production - it was featured on a hit single and used 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 1000 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.

Product Links
Company Product Sites:
[+] en.wikipedia.org
MSRP List Price: $1,500 - $3,000 - convert
Used Price: $35,000 - convert

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