I don't understand what a "digital " high level cable is?
I havn't read your previous post on this issue, but assume you are connecting to an integrated amp?
You may be referring to the high level Speakon connector that has 3 wires, yellow, red and black.
Yellow goes to LH positive speaker terminal, black goes to LH negative speaker connection and red to RH positive speaker terminal. You will not get sound if you connect black to amplifier chassis.
This is a standard Speakon connector cable, nothing special or "digital".
Your LH and RH speakers are connected as normal.
Perhaps I misunderstood your problem?
Gary
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