Rare 1966 Johnson Intonation Trainer Vintage Analog Synthesizer Tunable Keyboard

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You can actually find a couple of demos of the Johnson Intonation Trainer in the archives here.

"Very nice and ultra rare Johnson Intonation Trainer Synthesizer from 1966 with Tunable Keyboard.

Made by the E.F. Johnson Co in 1966 Waseca, Minnesota U.S.A.

Speaker in case, it can also connect to external amp or mixer.

Note from users:

Voicing - choose from four voices, basic sine wave to reedy / edgy

Scale Selector - choose between reference (tempered tuning) or tunable

Tunable Scale Controls - correspond to notes on keyboard and adjust pitch in tunable mode

Originally used to test the relationship of pitch-matching and pitch-discrimination abilities

It's FULLY polyphonic with vibrato etc. Cool for Drones and Experimental music, original manual inlcuded.
Conditions are at TOP! Excellent cosmetic conditions with an unique design and in perfect working order."

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Vintage Rare 1966 Johnson Intonation Trainer Synthesizer Tunable Keyboard

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Published on Aug 1, 2018 Sharief Hoffman

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You can find another video of one previously posted here.

"Very Rare to find Johnson Intonation Trainer
Made by the E.F. Johnson Co in 1966
Waseca, Minnesota U.S.A.

* Cool four-voice tunable electronic keyboard (scale selector switch offers choice of standard/tempered tuning or tunable modes)
* Originally used to test the relationship of pitch-matching and pitch-discrimination abilities

Highlights
* Three octave keyboard
* Scale Selector - choose between reference (tempered tuning) or tunable
* Tunable Scale Controls - correspond to notes on keyboard and adjust pitch in tunable mode
* Voicing - choose from four voices - - basic sine wave to reedy / edgy

* Speaker in case (can also connect to external amp, mixer, etc)"

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1966 Johnson Intonation Trainer microtonal analog synthesizer

Published on Apr 9, 2014 Golden Gate Estate Services·2 videos

"This is the 'Intonation Trainer', a specialized keyboard or synthesizer made in Waseca, Minnesota in 1966 by the E. F. Johnson Company. Better known for their high-quality amateur ("ham") radio equipment, Johnson made the Intonation Trainer for a few years in the '60s and marketed it to orchestra and choral conductors and, to a lesser degree, to musicians, for the purpose of training the ear to recognize when a note is correctly pitched.

Each of the 12 notes in the octave can be tuned to any pitch within about 5 steps of the given note, so microtonal music is possible. You can pitch the notes for just intonation, Pythagorean, well-temperament or any other form of the 12-tone scale. It also has four different oscillator waveforms (sine, square, triangle and sawtooth), it has tremolo, and is fully polyphonic. It has a reference tone generator (440-hz) for self-tuning and a separate tuning trim for each of the adjustable tones! Furthermore, it's fully self-contained with a built-in amplifier and speaker system, and the whole thing is enclosed in a fiberglass carrying case.

Intonation Trainers are quite rare; I only know of 3 other examples in existence. They were also hugely expensive when new -- $525 in 1966, which works out to about $4,000 in 2014 dollars.

This one is in excellent condition, both cosmetically and functionally."

VTG EF Johnson Intonation Trainer Keyboard

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"You are looking at a vintage E.F. Johnson Intonation Trainer.....37 Keys...really don't know much about this or what it is used for but it has a 1/4" Speaker out so I plugged it into my mixing board & it made some pretty crazy sounds. It seems like a synthesizer but not sure really. It comes in a hard case that has latches...it locks up but the handle you are suppose to carry it with is broke off."

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johnson intonation trainer synthesizer tunable keyboard

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"Johnson Intonation Trainer
Made by the E.F. Johnson Co.
Waseca, Minnesota U.S.A.

* Cool four-voice tunable electronic keyboard (scale selector switch offers choice of standard/tempered tuning or tunable modes)
* Originally used to test the relationship of pitch-matching and pitch-discrimination abilities

Highlights
* Three octave keyboard
* Scale Selector - choose between reference (tempered tuning) or tunable
* Tunable Scale Controls - correspond to notes on keyboard and adjust pitch in tunable mode
* Voicing - choose from four voices - - basic sine wave to reedy / edgy

* Speaker in case (can also connect to external amp, mixer, etc)"

CLICK FOR MORE »