The DX7 and the FM Digital Revolution — From Voltage to Computation

A Leap in Principle — From Voltage to Computation

The analog synthesizers of Articles 3–5 were “instruments of electrical circuitry,” shaping sound by controlling oscillation, filtering, and amplification with voltage. The Yamaha DX7 of 1983 leapt entirely beyond that principle. It made sound not with circuits but through digital computation — the first great transformation in which the electronic keyboard’s insides were replaced wholesale.

FM Synthesis — A Technology from Stanford

The heart of the DX7 is FM (frequency modulation) synthesis. It was discovered by John Chowning at Stanford University, and Yamaha secured an exclusive license for the technology.

• The frequency of one waveform (the carrier) is rapidly shaken by another waveform (the modulator)
• This produces complex overtones — and from these, timbre is built
• Six oscillating units called operators are combined via an “algorithm”

This is the exact opposite of analog subtractive synthesis (which removes overtones): the idea here is to generate overtones through modulation. The resulting sound is hard, glittering, metallic, and sharp in attack — the polar opposite of analog’s thick, round tone.

Rewriting the Sound of the 80s

The DX7 sold explosively (one of the best-selling synthesizers in history), transforming the sound of 80s pop:

• Sparkling electric bass (slap-bass style)
• Hard marimba and bell tones
• Bright brass

These distinctively FM sounds ring throughout songs of the 1980s. Much of what people identify as the “80s sound” is, in fact, the DX7.

“E.PIANO 1” — When the Fake Drives Out the Real

The DX7’s most famous preset is “E.PIANO 1” — an electric piano sound built with FM. Here, the paradox touched on in Article 2 reaches its completion:

• A real Fender Rhodes is heavy (over 60 kg), expensive, and difficult to maintain
• The DX7’s FM electric piano is light, cheap, stable in pitch, and connects via MIDI
• As a result, much of 80s ballad music became the sound of the FM electric piano, and the real electric piano vanished from the stage

The imitation drove the original out of the market — an event that most vividly demonstrated the question of “what counts as real” for the electronic keyboard.

Difficult Sound Design and Preset Culture

The DX7 had a weakness too — its sound design was extremely difficult. The interaction of six operators and 32 algorithms defied intuition, and editing on its small LCD and buttons was an ordeal. As a result, many users never designed their own sounds, and simply used presets or patch cards as they came.

This changed the culture of the electronic keyboard. It shifted away from the Moog-era ethos of “designing your own sound” toward “choosing from sounds already prepared.” The culture of modern sound engines, packed with vast libraries of presets, begins here.

Digital Synth-Pop and YMO

Digital synthesizers gave birth to new music. YMO (Yellow Magic Orchestra) sent technopop out into the world with microcomputer-controlled sequences and electronic sounds (straddling the transition from analog to digital). Alongside Germany’s Kraftwerk, they established an aesthetic of “rhythm and timbre that is not human, but machine.”

A Rhythm Machine Revolution Too — TR-808 / 909

Around the same time, though not keyboards, there were machines that would come to define electronic music: Roland’s TR-808 (1980) and TR-909 (1983) drum machines.

• They imitated real drums, but it was actually their “unnatural electronic sound” itself that came to be loved
• The 808’s thick bass drum became the foundation of hip-hop, and the 909 became the foundation of techno/house
• At the time they were unpopular and discontinued — only to be rediscovered secondhand and become the bedrock of dance music, in a striking irony

The Next Idea — Capturing Real Sound

FM digital synthesis created new sounds. But in parallel, a completely opposite desire was also growing — not to synthesize, but to record real sounds (acoustic instruments, voices, any sound at all) directly and play them from a keyboard.

The next article traces the arrival of sampling — how instruments like the Fairlight and the Emulator, and workstations epitomized by the Korg M1, brought “the sound of reality” into the electronic keyboard.