The 16-bit era: FM synthesis, samples and the SNES sound

Landmark scores of the era

1. 1991Sonic the Hedgehog Masato NakamuraThe Dreams Come True bassist wrote pop-styled themes within the Mega Drive's limits.
2. 1991Street Fighter II: The World Warrior Yoko Shimomura (with Isao Abe)Character themes gave each fighter a musical identity in arcades worldwide.
3. 1992Streets of Rage 2 Yuzo Koshiro (with Motohiro Kawashima)Club-influenced house and electro written using Koshiro's own music programming tools.
4. 1994Final Fantasy VI Nobuo UematsuA large cast of character themes on the Super NES sample hardware.
5. 1994Donkey Kong Country David Wise (with Eveline Novakovic and Robin Beanland)Made at Rare in Twycross, Leicestershire; its atmospheric tracks showed what careful sampling could do on the SNES.
6. 1995Chrono Trigger Yasunori Mitsuda (with Nobuo Uematsu and Noriko Matsueda)Mitsuda's first major score, finished with help from Uematsu.

Two philosophies: FM synthesis against sampled sound

The defining contrast of this era is between synthesis and sampling. A synthesiser builds a sound from scratch using mathematics; a sampler plays back a short recording of a real instrument. The 16-bit consoles took opposite sides.

Sega's Mega Drive used the Yamaha YM2612, a frequency modulation (FM) chip. It offered six channels, each made from four 'operators' that modulate one another to create complex tones. FM is excellent for punchy bass, bright brass-like leads and metallic percussion, but realistic acoustic instruments are hard to imitate. The Mega Drive also kept a Texas Instruments SN76489 for four additional simple channels, giving ten tone channels in total.

Nintendo's Super NES, released in Japan in November 1990 and in the UK in April 1992, took the sampling route. Its audio subsystem, designed by Sony engineer Ken Kutaragi, combined an 8-bit SPC700 processor with a 16-bit digital signal processor and 64 KB of dedicated memory. It could play eight voices of compressed 16-bit samples and apply effects such as echo. The catch was that 64 KB: every instrument for a piece of music had to fit into a space smaller than a single second of CD-quality audio.

Writing for the Mega Drive: pop songwriters and club producers

Sega's approach attracted composers who thought in terms of rhythm and production. For Sonic the Hedgehog (1991), Sega approached Masato Nakamura, bassist and songwriter of the Japanese band Dreams Come True. By his own account he had limited experience of computer music, and he described the hardware limits as extremely tight. His compositions were converted into data using an Atari ST running sequencing software, and the result was a set of bright, pop-shaped themes.

Yuzo Koshiro took a different path. For Streets of Rage 2 (1992), he wrote on an older NEC PC-8801 computer using a music programming language he had developed himself. Drawing on house, techno and electro, he produced tracks that sounded at home in clubs as much as on a console, with three contributions from Motohiro Kawashima. The soundtrack is often cited as an example of FM synthesis used to its strengths rather than as an imitation of an orchestra.

In arcades, Capcom's CPS-1 board paired a Yamaha YM2151 FM chip with an OKI sample chip. Street Fighter II (1991) used it to give each fighter a theme, most of them written by Yoko Shimomura, with additional tracks by Isao Abe.

Squeezing an orchestra into 64 KB: the Super NES approach

On the Super NES, the challenge was memory. Composers and sound programmers chose short samples of strings, brass, pianos and drums, then looped and pitched them to play whole melodies. Clever use of the echo effect helped short sounds feel larger.

Square's role-playing games pushed this hardware hard. Nobuo Uematsu's score for Final Fantasy VI (1994) gave many characters their own theme, an approach that relied on memorable melodies more than sound quality. Chrono Trigger (1995) was largely composed by Yasunori Mitsuda, with ten pieces by Uematsu, who joined when Mitsuda fell ill during development, and one by Noriko Matsueda.

A British studio produced one of the era's most discussed soundtracks. Rare, founded by Tim and Chris Stamper and based in Twycross, Leicestershire, made Donkey Kong Country (1994). David Wise wrote most of the music, with contributions from Eveline Novakovic and Robin Beanland. Working within the SPC700's limits, Wise used many small samples and leaned into a synthesised sound, and his underwater piece took several weeks to complete. It showed that restraint and atmosphere could matter as much as raw fidelity.

The Amiga, trackers and the MOD file

In Europe, the Commodore Amiga had already brought sample playback to home computers in 1985. Its Paula chip offered four hardware-mixed 8-bit PCM channels, two sent to the left speaker and two to the right. That stereo split gave Amiga music a characteristic wide sound.

In December 1987 Karsten Obarski released Ultimate Soundtracker, the first music tracker. Trackers display music as a vertical grid: each column is a channel, each row a step in time, and each cell holds a note, an instrument number and an effect. The program saved songs in its own MOD format, which bundled the samples with the note data. Because the format was compact and portable, it spread widely, and later trackers on the Amiga and PC built on it.

Trackers matter because they let people who were not programmers write music that a game could play directly. Many European game composers and members of the demoscene learned their craft this way, and some modern composers still use tracker-style tools today.

PC sound cards and the General MIDI question

On IBM-compatible PCs, music depended on what card a player owned. Early FM cards used Yamaha OPL chips, while some players bought more expensive MIDI modules. Because the same game could sound very different on different set-ups, composers often wrote several versions of their music.

This is also the period in which adaptive music systems took shape on PC. LucasArts introduced iMUSE in Monkey Island 2: LeChuck's Revenge (1991), allowing music to change smoothly in response to the player. We cover that story in the adaptive and modern era.

By the mid-1990s, CD-ROM drives were becoming common, and they would make many of these hardware differences matter less. The next chapter, CD audio and the 90s, follows that shift.

Character themes and the 16-bit storyteller

One habit that grew up in this era is giving individual characters their own music. Street Fighter II attached a theme to each fighter, so the music changed with every opponent. Final Fantasy VI went further, using themes for many members of its large cast and bringing them back at key moments in the story. On hardware that could not yet play voice acting at length, melody became a way of telling the player who someone was and how to feel about them.

This is the game equivalent of the leitmotif, a technique associated with opera and film. It works especially well in long games, where players hear a theme dozens of times and come to link it with a person or place. When that theme returns in a new arrangement, slower, in a minor key or on a different instrument, it can carry a great deal of emotion without a word of dialogue.

Composers of later eras, from orchestral role-playing games to small indie projects, kept using the approach. Our explainer on leitmotifs in games looks at how it is done and why it suits interactive stories.

Hearing the difference between FM and samples

A simple listening exercise shows the gap between the two approaches. Play a Mega Drive soundtrack and listen to the bass: it is usually sharp, buzzy and full of attack, a signature of FM. Then play a Super NES soundtrack and listen to the strings and pianos: they are recognisably recorded instruments, often softened by echo, but slightly muffled because of compression and limited memory.

Neither is better. Each suited different kinds of music, and composers who understood their machine wrote to its strengths. That lesson, write for the instrument you actually have, applies equally to an orchestra, a synthesiser or a game engine.