Sound Objects

Sound objects are the core assets of an Amplitude project. They define the various audio samples to be played and how to play them.

Amplitude supports 03 (three) kinds of sound objects:

  • Sound: The most basic sound object. It references a single audio file.
  • Collection: A container sound object. It manages a set of sounds and decides how and when to play them through a scheduler.
  • Switch Container: A container sound object. It can automatically play or schedule the playback of a sound object (Sound or Collection), according to the active state of a specific switch.

Each of those sound objects has in common the following set of properties:


uint64 required

A unique identifier for the sound object. This will be used later by the engine and other sound objects to get a reference to this one. This value should be different from 0.


string required

A unique name for the sound object. This may be used in runtime to access the sound object’s instance from the engine.


uint64 optional

With this property you can specify a special effect to apply to the sound object when played, by giving the id of that effect.


RtpcCompatibleValue required

The gain property stores the value of the gain (the volume) of the sound object. The value should match the schema of a RtpcCompatibleValue object.


uint64 required

This property stores the id of a bus object, on which this sound should be played. A sound object can only be played by one bus at a time.


RtpcCompatibleValue required

This property affects how the engine will prioritize this sound object relative to all others. When the engine is out of active channels, sound objects with low priority are muted when a play request is made with a sound object with higher priority. The value of this property should match the schema of an RtpcCompatibleValue object.


Spatialization default: None

The spatialization property specifies how the sound object’s gain should be adjusted based on its distance from the attached listener. It can have the following values:

0NoneNo spatialization is made, sound objects are played at their regular gain.
1PositionThe gain is adjusted based on the distance to the attached listener.
2PositionOrientationThe gain is adjusted based on the distance to the attached listener and the entity’s orientation. This means that the scope of this sound object should be set to Entity


uint64 default: 0

Specifies the ID of the Attenuation Model to use on the sound object. This property takes effect only if the sound is spatialized (the spatialization property is set to a value different from None). A value of 0 means that no attenuation will be performed, even if the sound is spatialized.


Scope default: World

With the scope property, you can control how the playback data is shared between each sound instance. The allowed values are:

0WorldAll sound instances will be treated as one object, so they will share the same sound data.
1EntityEach sound instance will be treated as one object per entity, and will only share sound data within that same entity.


string required

The fader property can be used to specify the fading animation to apply when the playback starts and stops. Its value should be a string containing the name of the animation. Amplitude comes shipped with a various set of faders:

  • Constant
  • ExponentialSharp
  • ExponentialSmooth
  • Linear
  • SCurveSharp
  • SCurveSmooth