HD Video SourcesThe 2114 adds four AV sources to an HLX matrix configuration for a maximum of 12 sources per system. Audio SourcesThe audio inputs are useful for AV sources, but can also be used as independent, audio-only source inputs for MP3, CD, or other audio sources or a mixture of audio and AV sources. How to Order Order the 2114 as part of a custom HLX Modular Matrix. Call your Audio Authority Account Manager with questions or to order your custom HLX configuration by telephone.