No, you must have one DSP as the MASTER, but it’s does not have to be a controller.

Is Meridian speak, the controller is the device that responds to IR signals from the remote.

IIRC the HD621 can not be a controller as it does not have a IR receiver.

What you need is for the Master DSP setup to be the controller and for it to send comms signals to the HD621.

Problem is that’s not an officially supported way to have the system, MConfig will be expecting to have a controller in the setup.

I’m not saying it won’t work, but it it’s a non-standard setup which adds doubt and uncertainty.

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