The sound source can be located in the vertical direction giving a full 3D spatial system around the surface of a sphere when combined with the azimuth property.
The following values are appropriate:
|level||On the same horizontal plane as the listener|
|higher||Approximately 10 degrees higher than the previous value|
|lower||Approximately 10 degrees lower than the previous value|
Values can be specified in degrees with the deg suffix. The values +90deg and -90deg correspond to the above and below keywords.