I received a Mirage S12 subwoofer and will be setting up my first home theater system. I think I know what all the controls on the back are for except one switch that is for phase. It can be set at either 0 or 180. Could anyone advise what the correct setting would be or what exactly this switch does. I have looked at the manual but I am still not clear. Thanks, Rob

Technically, it may be a bit hard to explain in words, but basically, you should try both positions and listen whether one position yields better bass than the other *at your listening position*. Changing the phase will affect how well the bass integrates with your main speakers. In this case, the phase switch inverts the sound waveform. Depending on where your sub is placed, you may find the sound at certain frequencies cancels itself out, and the phase switch/knobs is a way to compensate for that.

Ok thanks, so which is the standard position - 0 or 180? Also is this something that is controlled exclusively on the subwoofer or would there be controlls in the receiver for this also like there is for crossover frequencies?

0 is standard. Use it if you don't hear any difference.

Some receivers make phase adjustments as part of their automated set-up function, e.g. Pioneer's MCACC. It often shows up as the subwoofer's distance calculation.

I'm not aware of any receivers that let the user adjust phase manually, but there may be some. Your manual would explain if yours does.