Incorporate Sound Effects to Convey Information to Players
Sound effects should be considered an integral component of your game, as they can be employed for a wide variety of purposes. They serve to support events occurring within the game, including those that players can see on screen as well as those that remain out of sight.
Provide Feedback
Players rely on sound effects to receive feedback that enables them to make informed decisions and continue progressing through the game.
Sound effects should:
Aid Navigation Within the Game World
This pertains to navigation through diegetic sounds—sounds that originate from sources within the game world itself.
For more details on how to use auditory cues for navigation, refer to Auditory Navigation.
Communicate the State of the Game World
Awareness of the current state of various game elements contributes to narrative immersion. These states may relate to, for example:
Physical conditions.
In Jotun, the player character emits distinct sounds that players can easily associate with pain. This allows players to understand that their character is losing health.
Credit: Thunder Lotus. Footage captured by the author.
Movement.
Execution of actions.
Support Visual Feedback
For further information on reinforcing visual feedback through sound effects, see Provide Both Visual and Audio Feedback for Any Critical Information.
Evoke Emotions
To explore how sound effects can be used to enhance emotional engagement, refer to Apply Sound Effects to Strengthen the Atmosphere.
General Recommendations for Implementing Sound Effects
Acoustic Attenuation
Acoustic attenuation refers to the reduction in sound energy as it propagates through a medium. Implementing realistic acoustic attenuation in your game not only improves player feedback regarding in-game events but also offers additional benefits, as outlined below. You can incorporate the following real-world principles of acoustic attenuation:
Sound volume decreases as the player’s camera moves farther from the sound source.
This approach not only enhances realism but also reduces the number of simultaneous sounds being played, thereby clarifying auditory feedback.
Low frequencies travel farther than high frequencies.
This effect not only contributes to a more authentic sound environment but also causes distant sounds to appear muffled, helping players estimate their distance from the source. To simulate believable attenuation effects, consider the following options:
Obtain sound recordings captured from perspectives that replicate in-game situations.
Sound recordings of the Kulspruta M/39 heavy machine gun mounted on the Combat Vehicle 90. This video illustrates how capturing the same sound using multiple microphones placed at different locations results in recordings that exhibit varying attenuation effects.
Sound effects credit: Pole Position Production.
Use sound equalization and compression, if your sound was not recorded from the right perspective.
Example:
In S.T.A.L.K.E.R. Anomaly, the gunfire produced by an enemy NPC firing an assault rifle from a long distance—approximately dozens of meters—sounds noticeably muffled. This muffled sound serves as a valuable auditory cue, effectively conveying the distance between the enemy and the player character.
Low frequencies are less attenuated than high frequencies when obstacles exist between the sound source and the player.
Audio Clip Length
Minimize the length of your sound effects by removing unnecessary audio tails. Benefits of trimming include:
Fewer concurrent sound effects, resulting in clearer player feedback.
Faster release of audio channels, allowing new sounds to play more quickly.
Priorities: List of Sound Effects for Implementation
Begin by implementing sound effects that are essential to gameplay. Less critical sounds can be added at a later stage. When setting priorities, start with sounds that:
Provide vital feedback about the game’s mechanics.
Example:
Player character sounds indicating a near-death state or enemy sounds that inform strategic decisions.
- Strongly evoke emotional responses.
Example:
Audio cues indicating danger, such as collapsing structures or environmental hazards.
Priorities: Which Sound to Play at a Time
To manage device performance effectively, your game should limit the number of sound effects played simultaneously. Prioritization allows you to determine which sounds should be played at any given moment.
When the maximum number of sounds is reached, your game must decide which ones to continue playing and which to suppress based on assigned priorities. Organize your audio files by priority, and begin with a manageable number of priority levels.
When assigning priorities, consider the following:
The game should favor high-priority sounds over those with lower priority.
It is possible that a high-priority sound may be far from the player and barely audible, while a low-priority sound close to the player may be suppressed despite being more perceptible.
An excessive number of priority levels can become difficult to manage.
Priorities: Volume
Sound effects that are essential to gameplay progression should be louder than ambient sounds and background music. However, these should not exceed the volume of spoken dialogue that is crucial to the game’s narrative.
Higher-priority sound sources should be played at greater volume levels than those with lower priority. Use the provided table to assign importance to various sound sources, with priority level “1” representing the highest priority and corresponding volume.
Variations of the Same Sound
Providing different variations of the same sound is beneficial for several reasons:
In reality, no sound is ever reproduced identically each time it occurs. Offering multiple versions enhances the realism of your game.
Repetition of identical sounds can be fatiguing to players. Varied sound versions reduce auditory fatigue.
Consider the following methods to implement sound variations:
Acquire multiple distinct recordings of the desired sound effect.
Introduce slight randomization in pitch and volume—preferably within a ±20% range—to avoid producing artificial results.
Play variations in a randomized sequence, ensuring that no sound is repeated consecutively.