Music

Music, a type of audio asset, is included in most visual novels for a variety of reasons, including emotional emphasis, player immersion, and underscoring characters' personalities.

Types of music

• Music that plays throughout the majority of a visual novel is called Background Music or BGM.
  • Looping music is music that can repeat seamlessly without a gap or noticeable break, and is often used as background music.
• A piece of music associated strongly with a character is called a Character Theme.
• A piece of music that plays during the title menu is called Title Theme.
• A piece of music that plays with an animated introduction to a visual novel is often called Opening Song if it features singing or Opening Theme, similar to the opening themes of television shows.
• A piece of music that plays during the credits is often called a Credits Theme or Ending Theme.
  • In visual novels that have multiple endings, the music is often referred to as the character, event, or ending type (good, bad, true, etc.) ending theme. E.g., 'The Good Ending Theme'.
• Some music may occasionally fall into the category of sound effects and vice versa.
  • A small tune that accompanies a specific event, such as the arrival or introduction of a character, the solving of a puzzle, or choice-making is called a stinger.
  • Music that's performed or heard by characters in the story is often called diegetic music.

Functions of music in games

Some functions of game music, as described by Winifred Phillips, are:

• Putting the player in a specific state of mind, like putting players into a hyper-alert state in horror games.
• World building by immersing players through, for example, use of instrumentation that reflects the time period or location the game is set in.
• Setting the pace by underlining the excitement level.
• Reflecting a player's action and the state of the game by, for example, playing a game over theme when the player has lost or by changing switching the currently playing track to a cheerful one when something happy happens.
• A piece of music can be used for branding and may serve as an instantly recognizable theme that is connected to a game or game series.
• Demarcation, meaning creating music that is distinctly different from the rest of the soundtrack to strongly delineating in-game locations or outlining differences between gameplay types.

Dynamic music

The terminology surrounding dynamic music is often vague and contradicting. As such, terms like dynamic music, adaptive music, and interactive music are sometimes used synonymously, while some composers and scholars distinguish between them, sometimes providing definitions that are distinct from other authors'. The most widely quoted definitions of these terms can be found in Karen Collins' Game Sound.

Dynamic audio: Any audio designed to be changeable, encompassing both interactive and adaptive audio. Dynamic audio, therefore, is sound that reacts to changes in the gameplay environment and/or in response to a user.

Adaptive audio: Adaptive Audio refers to sound that occurs in the game environment, reacting to gameplay, rather than responding directly to the user.

Interactive audio: Sound events occurring in reaction to gameplay, which can respond to the player directly.

The difference between adaptive and interactive audio is, however, not clear cut. Richard Stevens explains that "[w]hether things happen because the 'game' instigates them or the 'player' instigates them is up for much debate […]. The game may instigate an event, but it only does so because the player has entered the area or crossed a trigger point – so whether this is 'game'-instigated or 'player'-instigated is probably a matter of debate." Some authors have therefore chosen to call music interactive that player's have a direct and conscious effect on (for example in music games), or music that the developers intended the player to interact with. Additionally, there are definitions of dynamic music that optionally define variability as one of its feature. Variability refers to change based on random chance. Game developers can implement dynamic music into a game by using the built in features of the engine or coding the functionality into the engine themselves. They can also use audio middleware such as FMOD or Wwise to potentially simplify the implementation of dynamic music. Composers have found different ways to manipulate music to make it more dynamic. The following is a non-exhaustive list of examples.

Replacing music

Completely replacing a piece of music due to changes in the gameplay environment and/or in response to a user is also regarded as dynamic audio. There are several ways to implement music in this way, as there are many ways in which one can transition 1. form one audio track to another, 2. from an audio track to complete silence or 3. from complete silence to an audio track. These techniques could be subsumed under the term horizontal change (oftentimes called 'horizontal resequencing').

• Hard cut and/or sudden start: The prior audio track suddenly stops playing (hard cut) or the next audio track starts playing suddenly (sudden start).
• Fade out and/or fade in: Fading out means that the volume of a track is gradually reduced to zero. Fading in means that the volume of a track is gradually increased from zero to its target loudness (usually a track's full volume). There can be a pause of variable length between the prior audio track fading out and the next audio track starting to fade in. There are different forms of fades, like linear, logarithmic etc.
• Crossfade: The prior audio track starts fading out while the next audio track fades in at the same time. The form of the fades can vary (linear, logarithmic etc.).
• Musical transition: A transition is added to the prior audio track as it receives the command to stop playing. This transition is oftentimes a music snippet that is seamlessly added to the stopping piece to conclude it with more finality than a fade could or to transitions into a new piece.

Manipulating music

Instead of transitioning from one distinct piece of music to another, it's also possible to manipulate a singular piece of music. Some musical elements that can be adjusted are:

• Pitch
• Speed
• Volume
• Panning
• Manipulation of notes - Manipulating the notes of a piece of music in MIDI format, for example, to alter its mode, harmonic progression, melody etc.
• Vertical change (oftentimes called 'layering' or 'vertical re-orchestration') - Instrument layers are added, removed, or replaced.
• Reverb
• Echo
• Equalization

The distinction between music replacement and manipulation is not clear when it comes to horizontal change. If a piece of music transitions to another section within the same piece of music or an alternative version of the same composition, then it could be defined as music manipulation making use of the horizontal change technique.

Interacting with music

There are cases where developers have implemented music in a way that motivates players to consciously change it. Triggering musical events leads to some sort of reward, lets the player progress through the game, or is the purpose of an area or a specific object, even if interacting with it does not lead to any tangible rewards. This type of music can employ the same music manipulation techniques seen above.