My Denon has 2 trigger outs. 2 Jacks, instead of one. So that's part one, you need to have a 1/8" DIN cable connecting the Yamaha trigger out to the ADA1500 trigger in.

My Denon is triggering my ADA1500. It could be either the cable, the Yamaha, or the ADA1500. Do you have another device that can send a trigger? If so, hook it up to the ADA1500 with a 1/8" DIN cable.

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