Passed as argument of GM:EntityEmitSound.
Sounds prefixed with ) tell the sound engine that it is a spatial sound; this allows the sound to emit from a specific location within the world.
Sounds prefixed with ^ tell the sound engine that it is a distance based sound. The left channel of the .wav is the 'near' sound that will play when the sound originates close to you, and the right channel is the 'far' sound that will play when the sound originates far from you.
Even if the SoundName value is changed, the OriginalSoundName value will remain the same.
Sounds may be returned as soundscripts (for example, "Weapon_357.Single") instead of the sound's file path. You can use sound.GetProperties to retrieve the actual file path.
If equal to 0 or CurTime(), the sound is played immediately. If greater than CurTime(), the sound is played with a delay. If less than CurTime(), part of the sound is skipped.
There are approximately 134 different presets defined by the Source engine between 0 and 133. These presets represent different types of 'rooms' or environments.
This determines how fast the sound drops away. A higher value means the sound can be heard farther away.