Roland GR-500 (1977)

Roland's first guitar synthesizer wasn't a box you plugged a Strat into. It was a complete system, guitar and all, that cost less than two grand and split six strings into six voices.

Overview

The GR-500 is one of the first guitar synthesizers anyone actually bought. It arrived in 1977 as a complete system rather than an add-on converter. Roland shipped it with its own specially equipped guitar, built in partnership with FujiGen. You couldn't bring your own Les Paul. The synth module and the guitar were a matched pair, and the period press said so: Modern Recording (August 1977, p.43) announced the system at a retail price under $2000, with a six-voice polyphonic output, one voice per string, and separate polyphonic ensemble, bass, solo, and external synthesizer sections. By the following January the same magazine was calling it the GR-500 Paraphonic Guitar Synthesizer System (Modern Recording, January 1978, p.37). "Paraphonic" was Roland's coinage from "parallel" plus "phonic," a word that described the architecture more honestly than "polyphonic" did.

In practice that meant six strings, six voices, each string tracked and routed independently. The guitar's output ran through a split pickup into the synth module, and the module broke the signal into the four working sections plus the external interface. The solo section used last-note priority, so the most recent note wins, the way a monosynth behaves. The polyphonic ensemble handled the chordal work. The processing chain, per the January 1978 write-up, included ADSR and AR envelope generators, an LFO, a high-pass filter, sample-and-hold, a noise generator, and a ring modulator. That's a serious analog toolkit for 1977. Much of the VCF and VCA circuitry was reportedly based on Roland's earlier analog monosynths.

Under $2000 in 1977 bought you the synth module and the dedicated guitar together, not a converter that assumed you already owned a suitable instrument. Add up a synthesizer, a guitar and the pitch-to-voltage hardware needed to make them talk, and the GR-500 looks more like a package deal. Roland's own advertising in the period leaned on the "new dimension of creative possibilities for the guitarist" line, which is marketing. The underlying claim was that a guitarist could access synthesis without becoming a keyboard player, and that was new.

Key Features

Six Voices, One Per String

The headline number is six, and it's not a polyphony spec in the keyboard sense. Each string gets its own voice, so the GR-500 can sound six independent notes at once. A chord on the guitar becomes a chord in the synth, with each note tracked separately. Modern Recording (August 1977, p.43) led with exactly this: a six-voice polyphonic output, one voice per string. The tracking was the hard part, and the period documentation is candid about it. Separating six signals from string vibration and picking up only the fundamental was described as a difficult engineering problem, one that took years of development to solve.

Four Sections Plus an External Interface

The module splits into a polyphonic ensemble, a bass section, a solo section, and an external synthesizer section. The polyphonic ensemble is the chordal engine. The bass section has its own envelope controls, and Roland's report in Sound Arts (March 1978, p.2) described those controls as capable of producing tones resembling string bass, electric bass, strings, or tuba. The solo section is the lead voice, using last-note priority so it behaves like a monosynth. The external section lets the GR-500 interface with outboard synthesizers such as the Roland System 100 or System 700, with separate outputs provided. That made the GR-500 a controller as well as an instrument, so a guitarist could drive a rack of Roland gear with the same strings.

Split Pickup and 24-Pin Interface

The guitar's special pickup system fed the synth module through Roland's own 24-pin interface, a proprietary connection that kept the guitar and module locked together. The GS-500 controller used a special pickup system, and the split pickup drove the sections. The bass, the ensemble and the solo voice all derived from the same string signal. The 24-pin cable is also why the system is inseparable. Without the specific GS-500 guitar controller, the GR-500 synth offers limited functionality, because it was designed from the ground up to work with that one instrument. Owners who lose the guitar are left with a module that can't do much on its own.

No Memory, Sliders Instead

There is no memory to store settings. Every patch is a physical position of the sliders, which adjust the VCO, VCF, VCA, and LFO sections. That's a limitation by any modern standard, but it's the state of 1977 technology, and it makes the GR-500 a live-performance instrument rather than a preset machine. A third-party "patch" memory floorboard called the PC-50 was available as an accessory. The sliders themselves are the interface, so the VCF cutoff is right there and not buried in a menu.

CV and Gate Output

Roland equipped the GR-500 with a CV and Gate output, which in pre-MIDI days was the universal language between synthesizers. That output let the guitar drive other analog gear, including the System 100 and System 700 named in the period press, and presumably anything else that spoke CV/Gate. It's a guitar-to-CV converter as well as a self-contained synth, and the six-voice architecture means it can send six independent control voltages if the receiving gear can handle them.

Historical Context

The GR-500 was announced in 1977, the same year Roland and FujiGen formalized their partnership as Fuji Roland Corporation through a joint capital investment. Roland was already deep into synthesizers, and the guitar was the next step.

The live setup described in the same report had the guitar's lead sound coming from center stage while the bass section was panned to the far right. The GR-500 could place different voices in different parts of the stereo field. It reportedly laid the foundation for the very successful Roland 24-pin guitar synthesizers that followed a few years later, the GR-300 and GR-700 among them, and the 24-pin interface itself became a Roland standard. These were pre-MIDI days.

Collectibility & Value

Current market information is thin. No exact Roland GR-500 listings were live on eBay at the time of writing, and the specialist dealers who handle this gear list it as currently sold out. One recently sold a unit described as fully refurbished and in exceptional electronic, mechanical and physical condition, reportedly hardly played when they acquired it. Another sold a serviced example with warranty in mint condition in its original box. No actual prices appear in the available record. The GR-500 is consistently described as a rare vintage instrument, and the complete-system requirement of module plus GS-500 guitar plus the 24-pin cable is the main reason. A module without its guitar is a paperweight, and a guitar without its module is a curiosity.

Documented modifications exist. The March/April 1981 issue of Polyphony magazine published the first list of Roland GR-500 modifications, and follow-up pieces on modifying the GR-500 and further comments and mods circulated in the same community. A modified unit isn't necessarily a red flag, but a buyer should know what was done. No common failures, repair procedures, or parts availability information appears in the available record, so a buyer should assume the usual risks of a 1977 analog instrument with a proprietary interface and no service documentation in circulation. The GS-500 guitar alone weighs in at more than 11 pounds, which is worth knowing before a three-hour set.

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