This will work fine for one - the Ultra will just look like a master speaker to the 861 to all intents and purposes, provided it's in variable mode, of course!

As soon as you add another one you're into the joyous world of whether more than one master speaker is a good/bad/terrible idea.

You also get into the physical world of the SpeakerLink connection and particularly how comms are arranged within it. SpeakerLink does not support more than one master and expects that master to return slave comms which are then distributed to all the other sockets on the controller as just "comms". The output to the other Ultras will be indeterminate.

So the expectation is that synchronisation of volume control changes will be an issue (the multiple master problem) and that you'll need some custom SpeakerLink, bridging to comms return from the "master", or use 5C cables to get comms to the other 2 Ultras.

Julian

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