Don't forget to add a Y extension to the subwoofer end of the RCA cable. It gives you a much better sound.
Hey Blu, what do you mean by adding a Y extension to the sub ?
Anything that I miss out? Any reading on this? Interesting..
This answer is waaaaaaaaaaaaaaaaay late, but just in case you notice this response:
The Y-Adapter connects to the digital-RCA (the cable that goes from the receiver to the sub) on the side going to the sub. The Y adapter splits the signal into two cables with the RCA ends, which basically allows you to simulate hooking up two separate cables to the sub, since all it needs is signal... the internal amp will boost it anyway.
*Many subs have dual-rca inputs. So using both of them is better then using only one
Rather than having you subwoofer cable just going into one of your 2 inputs (red/white) use a Y connector so that the sub cable feeds both inputs. Gives better bass.
Sorry, I hadn't realized that JPBostin had already explained it quite eloquently.
I know this is a bit late but here's my input.
In the days of stereo you would normally hook up a preout to a powered sub and would adjust the crossover and level for both. Most subs at the time did not have signal detection to tell if a stereo or mono signal was used and the low pass filter would send both low freq signals to a buffer and the sub would amplify in mono. This would also allow independent subs for left and right channels, until Pro Logic and DD were created/developed.
Where a down mix was needed to perform base management vs. running 6 channels of preout to a sub the receiver did the work and one connection to the sub was all that was needed.
Nowadays most subs can detect if a two channel signal is hooked up and will compensate for this. In fact you could make the sound worse by using a Y connection as this has been known to introduce noise into systems. When you install a Y splitter on the sub cable all you are doing is doubling the strength of the input signal. The most you can expect to gain from this is +3 dB increase in sound pressure.
You can accomplish the same thing for free just by upping the sub level in your AVR.
The Y splitter does not provide any additional performance or sound pressure that could not be recreated by increasing the sub volume control. As an example if you have 1000 watts to play with you can cut it anyway you like but its still is and will always be 1000 watts.
The only time I would recommend using a Y splitter is if you are experiencing difficulty getting the sub to wake from "sleep" mode that would only be solved by cranking up your sub level well into the positive to get satisfactory auto-on performance.
IMO, you are far better off checking you sub and AVR manual to see which is the best way to hook it up. If it doesn't say then contact either manufacturer to get the info straight from the horses mouth.