RMI 368X Electra-Piano & Harpsichord
Eighty-five pounds of chrome-legged solid-state piano - three instruments in one box, and not a string anywhere to go out of tune.
Overview
Rocky Mount Instruments pitched the 368X bluntly. Combos were tired of hauling an acoustic piano that wouldn't stay in tune, so here was a box with no strings and no struck bars to drift. The 368X is the "X" variant of the 368 Electra-Piano & Harpsichord, and RMI's own literature describes the 368 as the second generation of the 300 series of portable keyboards. The brochure calls the 368X "another out-of-this world innovation," which is the space-age salesmanship you'd expect from a subsidiary of Allen Organ Company in Macungie, Pennsylvania. The manual even points you toward "your space age music dealer."
Underneath the marketing, the 368X is a fully transistorized keyboard - all solid state, no tubes - built around 68 separate tone generators, one for every note on the 68-note keyboard. RMI's documentation is candid about why that approach cost more than the alternatives. Individual generators gave a properly scaled piano tone, let the instrument perform in ways other systems couldn't, and bought a high degree of reliability. Whether that last claim held up over decades is a question for the service bench.
The stop tablet layout is where the "three instruments in one" billing comes from. Seven tablets run across the panel: Piano, Piano PP, Harpsichord, Harpsichord PP, Lute, Organ Mode, and Accenter. Two more controls sit on the same board - Bass and Volume. The Accenter adds a percussive attack to the harpsichord or lute voices when you want it. Organ Mode lets all the stops sound as an organ without the normal percussive decay. Owners report that the Lute stop doubles as a useful electric bass voice, since the keyboard runs a full 68 notes down to low F. RMI's own sample-tone notes suggest that application, along with a "honky-tonk" piano made by depressing the Piano and Harpsi stops together. The Bass control is a sliding fader on the stop panel that lets you dial in as much low-end power as you like, and RMI's copy promises "a startling effect of sudden waves of bass tones" if you lean on it.
RMI claimed the individual keys are completely interchangeable and individually adjustable, with a quiet action carrying "all the excellent characteristics and quality associated with a wood action." That's a manufacturer claim, not an independent measurement. The chrome legs are self-contained - they fold out for setup and fold flat for carrying - and the whole capsule is listed at about 85 pounds. RMI's own materials are inconsistent on weight, with some copy claiming "under 80 pounds," so treat the figure as approximate. Closed up, the instrument measures 9 3/8 inches high, 42 5/8 inches wide, and 23 3/8 inches deep. Open, it stands 35 3/4 inches tall on the same footprint. Power draw is listed at a mere 10 watts from 105-125 volts, 60 cycles.
Expression and sustain come from a standard foot control unit with two pedals. One provides full-range expression from silence to full output, and the other produces piano sustain. The foot control connects via two cables with differently sized plugs, so mis-plugging is physically impossible. A permanently attached line cord and a 10-foot shielded cable with jack let the piano feed an amplifier directly. There's an AC outlet under the instrument so the amp can be switched on and off with the piano itself. RMI recommended its own RMI-140A amplifier for best results - a special-purpose unit with a separate treble system built to flatter the instrument's upper range - though the manual concedes the 368X will work with any high-quality music amplifier.
RMI's July 1, 1977 retail price list puts the 368X at a suggested list of $1,195.00. The companion 360-series audio systems ran $825 to $895 depending on cabinet, and the 360 amp head alone was $475. It was clearly positioned as a working musician's tool rather than a toy.
RMI's service notes cover the 368 and 368X together. They include a fix for sticking and/or clicking keys on the Electra Piano, a procedure involving shimming the keybed with metal washers. That fix is explicitly marked "NOT APPLICABLE TO MODEL 368X OR MODEL 668X," which tells you the X-series keybed was revised. Other service subjects include curing a dead note, tracking down crackling noise accompanied by volume rise or fall on certain notes, and organ-mode cipher with the sustain pedal. Generator tuning is a manual procedure, done by ear against a 440-cycle reference, with each successive interval deliberately tuned about 1-1/4 cycle flat to even out the temperament.
The 368X is not a synthesizer in the patch-cable sense, despite the tone-generator architecture. It's a preset keyboard with a fixed palette of piano, harpsichord, lute, and organ voices plus the Accenter and Bass controls. Collectors are usually chasing the Electra-Piano sound as heard on records, or an instrument that does a credible piano impression with zero tuning maintenance. The chrome tone-selector panel and black covering are period-correct and distinctive, and the self-contained legs make it one of the few vintage keyboards that sets up without a stand.
Period press coverage of the 368X in the audio magazines is thin in the sources available here. The surviving chunks from Mix and Sound On Sound don't contain substantive 368X reviews, so any claims about how contemporary critics rated it would be guesswork. RMI built the 368X to solve a specific, practical problem for working bands, and the documentation shows a company that thought hard about portability, reliability, and serviceability. Whether an individual unit still delivers forty-odd years later depends almost entirely on how it's been stored and whether anyone has kept the generators in tune.
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