Source:getFalloff

Returns the volume falloff of the Source, which causes it to get quieter as it gets further away from the listener.

minDistance, minVolume = Source:getFalloff()

None

Name	Type	Description
minDistance	number	The distance at which the volume starts to decrease.
minVolume	number	The minimum volume for the falloff. For example, .25 clamps the falloff to 25% of the source's volume. Note that other effects like cone and occlusion can still decrease the volume further. The falloff volume factor gets combined (multiplied) with other volume factors.

Notes

The formula for falloff is:

if distance > minDistance then
  volume = volume * math.max(minVolume, 1 / (1 + distance - minDistance))
end