A Retro Synthesizer Built From a Sega Genesis Console

Before Sony came along with the PlayStation and Microsoft with the Xbox, Nintendo’s biggest competitor in the North American market was Sega. While Nintendo was crushing it with their fourth generation Super Nintendo Entertainment System (SNES), the Sega Genesis (called the Mega Drive outside of North America) wasn’t far behind. Both were 8-bit systems with similar specifications, but they differed dramatically when it came to generating sound. The SNES had an advanced DSP (Digital Sound Processor) that could produce 8 voices from 16-bit audio samples, while the Genesis used a Yamaha YM2612 FM synthesizer. YouTuber Sam Battle of LOOK MUM NO COMPUTER built a synthesizer using a Genesis and its YM2612 chip.

FM synthesis can best be described as the sound of the 1980s. Frequency modulation synthesis was an early technique for generating “high quality” digital sound in a small and affordable package. It was pushed hard by Yamaha in particular, who sold many FM synthesizer modules. Those include the SFG-01 and SFG-05 modules, which were built into the Yamaha CX5M MSX 8-bit microcomputer that was marketed as a “music computer” and even had a MIDI keyboard accessory. Eventually, Yamaha was able to miniaturize their FM synthesizer technology down to a single IC chip, and that is what produces the sound in the Sega Genesis video game console.

To work with that and make custom chip tunes, Sam used a custom cartridge and MIDI adapter called genDMD that is made by Catskull Electronics. That provides access to the Genesis hardware, but Sam still needed a MIDI interface to connect to that adapter. For that, Sam constructed a massive interface that includes a full-size MIDI keyboard, control knobs for the various synthesizer operators, patch points for them, and sequencing capability. This gives him tactile control over all of the possible ways of adjusting the sound output through the Sega Genesis. Sam happens to be an accomplished musical artist himself, and is probably one of the few people who can actually put this build to good use. Be sure to stick around until the end of the video to hear some of the music he was able to produce with this synthesizer.