The 3D Audio scene graph profile provides for a set of BIFS scene graph elements for usage in audio-only applications.
|Level 1||Level 2||Level 3||Level 4|
|Maximum number of spatialized sources per scene||8||32||64||128|
|Number of temporal sections whose levels and time limits can be controlled individually for each source||1||1||2||3|
|Maximum number of independent late reverberation processes per scene||1||1||2||4|
|Maximum number of control frequencies in reverberation process filters, source directivity filters, and material filters||2||2||3||3|
 These spatialized sources can include ...