The cable supplied with the REL sub has three wires with the Neutrik Speakon connector for the high level input from the amp speaker binding posts to the sub. In a system with a single stereo amp, two wires connect to the + posts on the L and R channels and the third to the - post on the R channel only. With that amp connection, the Speakon goes to the unbalanced, high level input on the sub.
The balanced, high level sub input is for mono amps and two subs. The high level inputs on the sub are preferred for music. You can also connect the line level input from an HT processor at the same time for movies and use the input switch on the sub depending on the source.
The balanced, high level sub input is for mono amps and two subs. The high level inputs on the sub are preferred for music. You can also connect the line level input from an HT processor at the same time for movies and use the input switch on the sub depending on the source.