“We talk about music that originates from within the diegesis — and not from some non-diegetic player outside of it.”
— Axel Berndt
In a guest lecture on game audio, Dr.-Ing. Axel Berndt examined the role of diegetic music — music that exists within a game’s fictional world and can be heard, performed, or even disrupted by its characters. This kind of music, Berndt argued, is not background or emotional subtext. It is part of the world itself.
Berndt, is a member of the Center of Music and Film Informatics within the Detmold University of Music, working at the intersection of sound design, musical interaction, and adaptive systems. His lecture brought together commercial examples, music-theoretic distinctions, and design considerations to illustrate how music behaves differently when it belongs to the world rather than framing it from outside.
Inside the World: What Makes Music Diegetic
Diegetic music refers to music that originates within the game’s diegesis — its fictional environment. Berndt described it as everything “within this world”: sounds that characters can hear and react to, including wind, speech, and music performed or played through in-world devices.
“If someone switches the radio on, triggers the music box, sings a song, or plays an instrument… their music is also diegetic.”
Examples included a street musician in The Patrician, a pipe player at a party, and the bard at the start of Conquest of the Longbow. In Doom 3, a gaming machine plays music within the scene; in Oceanarium, a robot performs in a clearly defined virtual space. These are not aesthetic flourishes — they anchor music in the logic of the world.
Berndt contrasted this with non-diegetic music, which accompanies a scene without being part of it — such as a film score swelling during a battle. “There is no orchestra sitting on an asteroid during the space battle,” he remarked, highlighting the artificiality of non-diegetic scoring in game environments that otherwise strive for realism.
Sound That Can Be Interrupted
Once music is part of the world, it becomes subject to physical space, interruption, and interaction.
“The simplest type of interaction may be to switch a radio on and off, but there is much more possible.”
Berndt categorised musical interactions as either destructive — disrupting a performance — or constructive, where player input enriches or alters the musical output. In Monkey Island 3, players must stop their crew from singing an extended shanty by choosing responses that are woven into the rhyme scheme. Each interruption is musical and interactive.
“The sequential order of verses and interludes is arranged according to the multiple choice decisions the player makes.”
Such scenes turn performance into a mechanic. Music is not a layer applied to gameplay — it is the gameplay.
When Music Isn’t Polished — And Why That Matters
Berndt emphasised that diegetic music should not always sound flawless. Live performance in reality includes irregularities: tuning fluctuations, missed notes, imperfect timing. Simulating this can enhance believability.
“Fluctuations of intonation, rhythmic asynchrony, wrong notes — these things simply happen in life situations. Including them brings a gain of authenticity.”
He cited the harmonica player in Gabriel Knight, whose wavering tone subtly reinforces the impression of a street musician with limited technical control. Imperfection isn’t failure — it is context-aware design.
Berndt also warned against repetitive loops that expose the limits of a system. When the player leaves and re-enters a scene, and the same music starts again from the beginning, the world appears frozen. “We reached the end of the world,” he said. “There is nothing more to come.”
To counter this, he advocated techniques such as generative variation, asynchronous playback, and music that continues even when not audible — preserving the impression of an autonomous, living environment.
Games Where Music Is the Environment
Berndt’s second category of diegetic music is visualised music — where players engage not just with music in the scene, but with music as the environment itself. This includes rhythm games like Guitar Hero, Dance Dance Revolution, and Crypt of the Necrodancer, where music structures time, space, and action.
“What we actually interact with is music itself. The visuals are just a transformation — an interface that eases our visually coined interaction techniques.”
In Audiosurf, players import their own tracks and race through colour-coded lanes shaped by the waveform. In Rez, players shoot targets that trigger rhythmic events. These games represent a shift from music as accompaniment to music as system.
“The diegesis is the domain of musical possibilities. The visual layer follows the routines of the music.”
Berndt emphasised that this kind of interaction demands careful timing, expressive range, and sometimes even simplification to make musical gameplay accessible.
From Instruments to Systems
Not all music-based interaction takes the form of traditional games. Electroplankton allowed Nintendo DS users to create sound patterns through direct manipulation — drawing curves, arranging nodes, or triggering plankton-like agents.
“Interestingly, all these concepts don’t really need introduction. Give it to the players, let them try it out, and they will soon find out by themselves how it works.”
Berndt distinguished between note-level interaction (e.g. triggering individual sounds, as in Donkey Konga) and structural interaction, where players influence arrangement, progression, or generative systems. Both approaches are valid, but they ask different things of the player — and of the designer.
Designing with Music in Mind
Berndt’s lecture underscored a recurring principle: if music is situated in the world, it should behave accordingly. It must continue when out of frame, shift based on player presence, and reflect changes in the environment. When music is visualised or systematised, it should offer feedback and form, not simply decoration.
“Music as part of the world has to be interactive, too.”
This is not a stylistic preference — it is a design commitment. When music is embedded in the rules of the world, it becomes not only more believable, but more meaningful. It can reflect character, reinforce consequence, and establish rhythm within both narrative and mechanics.
Berndt’s examples — from Monkey Island to Rez, from ambient performance to interactive music toys — show how music can operate on multiple levels at once: as texture, mechanic, and presence. His lecture made clear that diegetic music in games is not a solved problem or a historical curiosity. It remains a rich site for experimentation and design.