The JBL Dante could be used without a 271, If you daisy chain comms to all your DSP speakers and type them as type 1.

You would need a Dante to SPDIF adapter such as the RDL for each pair of channels and the requisite network gear and software to set up the RDL's. You would only need to turn the speakers on and off and leave the volume at 87 and leave the volume via the JBL or leave the volume of the JBL at 0db and control the volume via the Master DSP. The JBL however uses the same firmware as the Arcam mentioned previously.

We have used Dante in the pro audio arena and it seems to be fairly reliable. All said, this would be a fairly easy DIY setup for someone with lots of legacy speakers as you could use traditional comms and the SPDIF input on the DSP's without a bunch of extra analog to digital conversion and no AC12/revivers or 271.

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