Dubreq Pianomate SN 421

via this auction

You can find a demo of one here.

"This is a Dubreq Pianomate analog synthesizer piano enhancer. Dubreq's Pianomate is a crazy box of tricks, designed to capture the tone of a piano creating an electronic & acoustic sound together like a hybrid synth. Two bars with sensors rest on the keyboard wired into the amp/speaker built into the Pianomate. The bars, treble/bass respond to piano playing, when the key is pressed the tonebar key drops down, creating the note. This results in a synth sound, that's warm but polyphonic. A 3-way rocker switch controls 'Balance' (bass, both, treble), another 3-way rocker selects 'Voice' (french accordion, organ, flute, jazz buzz). There are two volume knobs Pianomate & Mic. Another 3-way switch control vibrato. Between the two volume knobs is access to a small trim pot that allows fine tuning of vibrato speed. This Pianomate is in great condition."