Publish Date: November 9, 2020
Those already familiar with AVDECC control on Mac via the built-in "AVB Audio Configuration" utility, will notice a few changes in MacOS Big Sur. The method by which a Mac AVB Entity is added to the list of available audio devices in Audio MIDI Setup has now changed, such that a stream must be routed to the Mac first for it to populate in the Audio MIDI Setup "Audio Devices" list. This article goes through the workflow changes in Big Sur that users will need to be familiar with regarding AVB audio and how they relate to the Series III AVB Ecosystem.
First, let's launch AVB Audio Configuration by either of the two methods:
1) Directly from Terminal by typing in the command
2) From the UC Launch Window
When your Mac running MacOS Bir Sur is connected to your AVB network, you will need to select the Mac as an audio entity in "Simple Virtual Audio Entity" as usual
Once that's done you will see the Mac in the "AVB Entity Controller" list
You will also now see it in the "AVDECC Connection Matrix", although it will initially show an incompatible stream format
In order to correct this so that the Mac stream format matches that of the Series III Ecosystem, all Mac AVB streams must be switched to type "IEC 61883-6 AMB-24" at the desired sample rate
At this time, it is a good idea to ensure your Mac AVB clock is set as desired. In a Series III Ecosystem, the master mixer is usually the master clock for the AVB network, so the Mac Clock Source should be set to "Audio Input Stream 1"
Now you will see that the Mac streams are compatible with the rest of the Series III Ecosystem in the connection matrix. A stream should be routed from the master Series III mixer to Mac Input Stream 1, which will allow it to be available as an Audio Device in Audio MIDI Setup
NOTE: Routing an AVB stream to the Mac on MacOS Big Sur is the ONLY way for it to be used as an AVB audio device. Without doing so, it will never populate in Audio MIDI Setup as an AVB audio device. In previous MacOS versions, this is not necessary.
Once this is done, the Mac is now an available audio device in Audio MIDI Setup as shown in the "Audio Devices" window below on the left. In prior MacOS versions, the Mac first populates in the Audio MIDI Setup "Network Device Browser" shown on the right, and first must to be checked there before it populates in the Audio MIDI Setup "Audio Device" list. In MacOS Big Sur, this step is skipped and the Mac AVB Entity does not show in the Audio MIDI Setup "Network Device Browser".
Now the Mac can be used as an AVB Audio Device for direct recording and playback