CRR – Advanced Matrix

For most systems, there will never be any need to manually adjust the internal, rules-based routing of the Conference Room Router. Since there is an exception to every rule, it is possible to access and change the internal routing as needed. This can also be useful as a simple way to visually confirm the audio routing within the CRR.

To access the Advanced Matrix, right-click on the Conference Room Router, select Matrix Mode from the context menu, and select Advanced. On the CRR control panel, the button to access the Advanced Matrix replaces the Speaker Matrix button.

In the Advanced Matrix, it is possible to control all the crosspoints within the Conference Room Router regardless of whether the changes would be appropriate, based on the rules for a typical teleconference room, or whether a particular crosspoint could be expected to cause problems. This includes things such as routing a Far End signal back to its own output or routing microphone signals to the AEC reference.

If any changes have been made on the Advanced Matrix control panel, an “unlocked” icon will appear on the CRR processing object. This provides a visual indication that the CRR is no longer routing audio based on the standard rules. If the CRR is reset to default by clicking on the Default Settings button on the Advanced Matrix control panel, the “unlocked” icon disappears.

In some cases, there will be gaps in the Advanced Matrix control panel where crosspoints cannot be enabled. These gaps are not an attempt to prevent improper audio routing. The Conference Room router is a composite object made up of multiple matrix and gain primitives. Gaps in the Advanced Matrix control panel represent routes that do not exist within the composite object.

Stereo - Mono
The Advanced Matrix control panel also exposes the stereo to mono and mono to stereo compensation within the CRR. When sending mono signals to a stereo output, or stereo signals to a mono output, it is necessary to reduce the signal levels by 3 dB to maintain the same perceived mix. For example, when working with a stereo Program source and mono Far End sources, the mix heard through the stereo speakers should be the same as the mix being sent to the mono far-end. In order for the relative levels to be the same, the mono sources need to be reduced by 3 dB in the stereo outputs, and the stereo sources need to be reduced by 3 dB in the mono output. The CRR makes these adjustments automatically.

When working with a non-standard stereo field, this gain reduction value can be globally adjusted by right-clicking on the CRR processing object, selecting Stereo Mono Attenuation from the context menu, and selecting a different value.