World 10
Sound
Music, effects and silence: the half of the game people feel without noticing, and the words for asking for it.
Sound tells players what happened, where it happened and how much it matters, usually faster than the picture does, and most of them could not tell you it was there. It is also the part of a game people find hardest to describe, so requests come out as "make it more epic." With these words you can ask for what you mean: duck the music 9 dB under dialogue, randomise the pitch on the footsteps, bring the drums in when the guard sees you.
- WaveformsThe basic repeating shapes a synthesiser starts from. Each has its own stack of harmonics, the quieter pitches above the main one, and that stack is what makes it sound the way it does.
- ADSR envelopeFour numbers that shape a note's loudness over time. Attack is how fast it rises, decay how fast it falls to the sustain level, and release how long it takes to fade once the note ends.
- Low-pass filterA filter that lets low frequencies through and cuts high ones above a chosen point, the cutoff. Close it and a sound goes dull, as if heard through a wall.
- ChiptuneMusic written for, or in the style of, the sound chips of old consoles and computers. Those chips have only a few voices, each playing one note at a time, so every limit is heard.
- AmbienceThe constant quiet sound of a place: a low bed that never stops, plus small sounds scattered at random around you. Nobody notices it until it stops.
- FoleySounds of bodies and the things they touch, usually recorded by a person acting them out: footsteps, clothes, a hand on a door. The name comes from Jack Foley, who did this for early film.
- Diegetic and non-diegetic soundDiegetic sound exists inside the game's world, so its characters could hear it: a radio, a footstep. Non-diegetic sound lays over the world for you alone: the score, a menu click.
- AttenuationHow a sound gets quieter as you move away from it. A curve maps distance to volume, usually with a range inside which it is at full volume and a range beyond which it stops.
- OcclusionMuffling a sound because something solid stands between it and the listener, usually with a low-pass filter and a drop in volume. Games test this with lines or room graphs.
- ReverbThe thousands of echoes that follow a sound as it bounces around a space, blurred into a tail. Its length and colour tell your ears the size and material of the room.
- Pitch randomisationPlaying a repeated sound slightly higher or lower each time, or cycling through several recordings of it, which is called round robin. The two are usually used together.
- Voice limitingA cap on how many sounds can play at once. When a new sound needs a voice past the limit, the least important one is stopped: it is stolen.
- MixThe balance of every sound against the others, so that what matters can be heard. In a game it must change as play changes, so groups of sounds get saved sets of levels called snapshots.
- Dynamic range and loudnessDynamic range is the distance from the quietest sound to the loudest, in decibels. Loudness is how loud the whole game seems over time, measured in a unit called LUFS.
- DuckingTurning one sound down automatically while another plays, most often music under speech. A sidechain is the wire that does it: one sound's level controls another's volume.
- Silence as a toolRemoving sound on purpose: cutting the music, or even the ambience, before or during a moment. Silence is something you can play, as long as you have made noise beforehand.
- EarconA short abstract sound with a learned meaning, like a menu blip that means yes. It is a word in the game's language, and nothing in the real world sounds like it.
- StingerA short burst of music played over the score to mark a moment: a discovery, an alarm, a victory. It is written to fit the score, and can wait for the next beat.
- LeitmotifA short tune tied to one character, place or idea, and brought back changed as the story goes. The same notes can be heroic in one key and broken in another.
- Vertical layeringSplitting one piece of music into layers that all play at once in sync, then fading them in and out with the game. The music can change at any moment without a seam.
- Horizontal resequencingCutting music into sections and letting the game choose which plays next. Requests wait for a musically sensible point, usually the next bar line, so changes sound written.
- Adaptive musicA score that responds to what the player is doing, by bringing layers in and out, moving between sections, or both. The composer writes rules as well as notes.
- Musical feedbackPlaying the sounds of repeated actions as notes, often climbing a scale as a combo grows. The action becomes a tune, and the player can hear how well it is going.