Hi I have a question about my sub,when i set it up there was a cable that came with it that was a Y shape. The question is do i need this cable or can i put my sub cable direct into sub by one of the connections,thanks.
Correct - you can use one cable into the sub into the left input. Subs are mono - manufacturers only include left/right inputs on a mono sub for convenience incase you're using a L/R pre out for some reason but you only need to connect to one.