Trying to help a friend wire up two amps, a mixer and a crossover to two passive speakers and one passive sub woofer. One amp lacks a speakon inputs, I therefore connect the RCA. All summarized in the diagram below: I will greatly appreciate any assistance. As for now I only have two speakers playing. The sub is not playing.
Points for the illustration. Unfortunately, it is still impossible to see exactly how the system is connected.
Are you going from a balanced to an unbalanced connection at some point? If so, it's possible your pin out assignment on the connector is not correct for the connector/circuit you are feeding to or from.
Check your owner's manual for a clarification regarding which pin is hot at each connector. This could still be your solution if all connections are made in balanced mode. There is still a lack of consistency among manufacturers as to how their balanced connectors get wired.