Korg M500 Micro-Preset (1978)
Eight sounds, one VCO, zero apologies — the preset synth that traded editability for instant gratification.
Overview
At $495, the Korg M500 Micro-Preset wasn't priced like a toy, but it wasn't priced like a serious instrument either — and that was exactly the point. Launched in 1978 as Korg's first preset synthesizer, the M500 was aimed squarely at beginners who wanted to make music without first earning a degree in patch cords. The trade-off was absolute: eight preset voices, a single VCO, and no memory to speak of. What you saw on the front panel was what you got, and for a certain kind of player, that was liberation rather than limitation.
The timing mattered. In 1978, the synthesizer market was dividing itself between performance instruments for working musicians and experimental boxes for studio tinkerers. Korg's answer with the M500 was to split the difference — a machine simple enough for a first-time buyer but voiced with enough character that working players found uses for it. The 49-note keyboard (spanning F to F) gave it a legitimate range for melody work, and the monophonic voice meant you had to think like a horn player or a singer, not a pianist. The single VCO with waveshape switching offered just enough tonal flexibility to keep the eight presets from feeling like a cage.
Owners today describe it with affection and frustration in equal measure. "It's limited because of the presets. No editing. But that's the appeal for some," one collector notes — a fair summary of the M500's enduring charm. This is not a synthesizer for sound designers. It's a synthesizer for people who want to switch on, pick a voice, and play. There's an honesty to that approach that feels increasingly rare.
Key Features
The Eight Preset Voices
The M500's entire identity rests on eight round preset switches arrayed across the front panel: Bassoon, Oboe, Clarinet, Flute, Violin, Cello, Pan Flute, and Brass. These aren't approximations or starting points for further editing — they're the whole show. The preset selection itself is handled by C-MOS logic, a detail the manual mentions with some pride, and it means switching between voices is instantaneous and silent. There's no memory in the system — the manual states plainly, "This system has no memory — preset only" — so what you hear is what the factory decided a bassoon should sound like through a single VCO.
The voice quality punches above the price point. The strings in particular have aged well; one owner reports that "the strings sound amazing for a preset synth," and that assessment holds up. The Brass voice has a nasal insistence that sits well in a mix, while the Pan Flute demonstrates just how much character a simple waveshape switch can conjure. None of these would fool a session player into reaching for the M500 over a proper instrument, but they're musical and usable — which is more than can be said for many far more expensive synthesizers of the era.
49-Note Keyboard and Monophonic Voice
The keyboard spans 49 notes from F to F — roughly four octaves — which is more range than many preset synths offered. Because the M500 is monophonic (the manual lists "Voice: One" without elaboration), the extended range matters more than it might on a polyphonic instrument. You can jump from a bass line to a melody without running out of room, and the single voice keeps the architecture simple: VCO through VCF through VCA, with no detours.
The monophonic limitation is worth understanding before you buy. This is not a chord machine. It's a lead instrument, a bass instrument, a sound-effect generator. Players who approach it with that understanding tend to keep it; players expecting a miniature poly synth tend to sell it. One former owner admits, "I bought it but sold it later because it collects dust" — a common fate for any instrument whose personality doesn't match its owner's needs.
Controls: Pitch, Brightness, Volume
Beyond the eight preset switches, the front panel keeps things minimal: three rotary knobs for Pitch, Brightness, and Volume, plus a power switch and a headphone jack. The Pitch control functions as a master tuning adjustment, letting you drop the whole instrument or raise it to match other gear. Brightness is the filter control — the manual describes a VCF with presets, meaning the filter cutoff is pre-programmed for each voice, and the Brightness knob sweeps it from dark to edgy. It's a limited form of expression, but it's enough to shape the sound noticeably.
The absence of further control is by design. There's no LFO, no modulation routing, no envelope shaping — none of the parameters that make a synthesizer a synthesizer in the conventional sense. What you get instead is the ability to adjust pitch and filter response in real time while you play, which turns out to be surprisingly expressive for an instrument this simple. The panel layout is clean and legible, with the eight preset switches arranged in a row above the three knobs.
Connectivity: Simple and Stubborn
The M500's rear panel offers a single 1/4" output jack and nothing else of note. There's no MIDI — the spec didn't exist yet in any practical form when this was built — and, more surprisingly for a Korg of the period, no CV/Gate jacks either. This is a fully self-contained instrument with no external control options whatsoever. If you want to sequence it, you'll need to play it by hand or modify it. If you want to process it through effects, the output jack accommodates that easily enough.
Power comes from a DC 9V 300mA adaptor, which the manual specifies with unusual precision. That adaptor has become something of a sticking point for modern owners — as one forum poster puts it, "only issue is the power adaptor is hard to find." The M500 doesn't run on batteries, so losing or damaging the original wall wart effectively bricks the instrument until a replacement surfaces. It's a minor inconvenience in the grand scheme of vintage synth ownership, but worth knowing before you commit to a purchase.
Historical Context
Korg's legacy pages describe the M500 Micro-Preset as the company's first preset synthesizer, launched in 1978. A forum thread from 2020 corroborates that date, though a reply in the same thread suggests 1979 — a minor discrepancy that doesn't meaningfully affect the instrument's story. Either way, the M500 arrived at a moment when Korg was establishing itself as a serious synthesizer manufacturer, and the Micro-Preset line represented an attempt to reach buyers who found the company's larger instruments intimidating or unaffordable.
The M500 was designed to be an affordable entry-level synth for beginners, and the $495 price tag reflected that mission. One forum commenter notes that "this is similar to the later Yamaha CS-01," and the comparison is apt: both are preset-oriented, entry-level instruments that prioritize immediate playability over deep synthesis. The M500 got there first.
Period coverage of the M500 is thin — no professional reviews from the major audio publications of the era have surfaced. That silence is telling in its own way. The M500 wasn't aimed at the reviewers and the pros; it was aimed at the beginner in a music store who wanted to make sounds without learning signal-flow diagrams. Sound on Sound (UK, 1998, p.269) would later discuss the Micro-Preset line alongside other Korg instruments of the period, noting that these preset machines achieved "brief notoriety" — a fair epitaph for an instrument that was never meant to be a classic, only a gateway.
Collectibility & Market
The M500 Micro-Preset occupies an odd space in the vintage synth market. It's not rare enough to command serious collector prices, and it's not versatile enough to attract working musicians, but it has developed a devoted following among players who appreciate its simplicity and character. Recent Reverb listings show prices ranging from approximately $250 to $600 USD, with individual listings at $465 and $649 — a wide spread that reflects the instrument's niche appeal. Condition and the presence of the original power adaptor are the primary factors in where a given unit lands in that range.
Reliability is a non-issue according to available documentation; no common failures or recurring problems have been reported by technicians or owners. The C-MOS logic used for preset selection has proven durable over four decades, and the single VCO is a simple circuit that doesn't give much trouble. The main practical concern remains the power supply — the specific 9V 300mA adaptor isn't a standard off-the-shelf item, and replacements require some hunting.
Owner opinions cluster around two poles. Enthusiasts describe it as "a classic" and praise the preset voices, particularly the strings. Skeptics point to the inherent limitations of a preset-only architecture with no editing and no external control. Both perspectives are valid. The M500 Micro-Preset is what it is: a beginner's instrument from 1978 that happens to have aged into a charming oddity. It won't be the centerpiece of a serious synthesis rig, but for someone who wants to plug in, pick a voice, and play — no menus, no patching, no fuss — it delivers exactly what it promises.
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No exact Korg M500 Micro-Preset listings are live right now — these searches show current Korg and similar vintage synth gear on eBay:
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