I'm not aware that anyone has dissected a MMHR yet work out which pins carry what signals. I think the assumption of it using one twisted pair per AES channel is a fare one.

We know which pins are used for SpeakerLink AES channel, from this it should be possible, though experimentation, to identify the which MMHR pairs carry which channels.

Mined, I'd not chop up Meridian SL cable to find out, it would be cheep cat5 UTP patch lead.

Regards,
Carl

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