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"These were only made for a short time and from what I can find about them there was only 600 of them made. Here's your chance to own a very nice and clean one.

-everything functions as it should, has been reset to factory settings.
-This keyboard is in very nice shape, very little scuffing and signs of use, very clean!
-For whatever reason the cosmetic portion of the volume slider is missing, no problem using as it is or could be replaced easily.
-The unit was brought in from out of the country and was then professionally modified for use with 120V AC electricity, so to be clear, it is configured currently for 120 volt AC for the United States.
Here's some info from the internet:
The Technics SX-WSA1 puts you at the controls. Nearly all modeling parameters can be accessed in realtime by using various easy-to-operate controllers such as the Pitchbend and Modulation wheels, Realtime Controller, Realtime Creator, Key Touch and more. The Realtime Creator and Realtime Controller each allow you to control 2 parameters at one time (X-Y axes). The Realtime Creator knob maintains the last set position, while the Realtime Controller returns to its neutral position. In addition, up to six sets of parameters can be stored for each sound, allowing rapid assignment to the Realtime Creator or Realtime Controller! This makes it possible to control, for example, where you strike the drum surface, the mouthpiece angle on a flute, or the embouchure of a trumpet. These controllers give you the freedom to fully express yourself in your music. At last, your creativity is limited only by the imagination.
Sounds that are out of this world:
The Technics SX-WSA1 also gives you the power to create a virtually unlimited range of instrument sounds. For the first time, you're no longer restricted by the sound sets in your instrument. Imagine, you now have full control over the parameters for the driver and resonator. This lets you form unique combination sounds like a tom-tom "fusing" into a chopper bass, or a guitar with a flute resonator. Sounds can be "crossfaded" by key or velocity. Even more astonishing, you can construct virtual instruments that cannot be built in reality. Now, that's really out of this world!
With all these creative possibilities offered by the WSA1:
It would be a shame not to have sufficient polyphony. That's why this synthesizer features not one, but 64-note polyphony—the culmination of Technics' outstanding achievements in advanced LSI research. With 64-note polyphony, you have all you need fully orchestrate your music.
More outstanding features:
The Technics WSA1 features a large graphic LCD screen which makes its operation both intuitive and extremely user-friendly. The 16-track, 47,000 note Sequencer includes some graphical editing capability. There are two MIDI ports (IN/OUT/THRU) to allow you to make the most of the 32 MIDI parts available (32-part multi-timbral), and there are four line-level outputs (two stereo pairs) to get it all to tape or the PA. If all that isn't enough, there is an optional Output Expansion Board which provides four additional line-level outputs and an S/PDIF digital coaxial output. An optional Wave Expansion Board will provide you with access to even more driver sources. Acoustic Modeling, Real-time control, and 64-note polyphony, a 16-track Sequencer with enough MIDI parts and outputs to make the most of it. A large, graphical LCD screen to tie it all together in one powerful, easy to use package, Technics is all you need."
Additional specs below.