Originally Posted by Test123455
so if theres only a single RCA input, that means it is already summed?
Well, let me try to decipher your incomprehensible question:
so if theres only a single RCA input
As you are referring to an "INPUT", I will ASSUME you are referring to an input on the subwoofer. Subwoofers are MONO. They only provide a single sound source. An "input" on a subwoofer cannot guess what kind of signal it is being fed but, if you are hooking it up to a multichannel source, I am certain the designer of the subwoofer expected that you have already combined all of the necessary sources together when you plug something into its single input.
that means it is already summed?
If you are referring to a single RCA "OUTPUT" on an AVR, yes - the multiple channels in the AVR are already summed together at the single output to the subwoofer (dependent on the bass management settings in the AVR).