Difference between polarity and phase w/sub

Polarity refers to your speaker connections. + to + and - to - is normal. Phase refers to the inward or outward movement of the diaphragm of the speaker in relationship to the speaker producing the original waveform. For a variety of technical reasons I don't begin to understand, some of the equipment in the recording chain sometimes inverts the phase. Some people say they can hear the difference and so a switch that allows this to be altered in a transducer will give those folks who can hear it, suppossedly more accurate reproduction. Hope that helps.

The phase switch for a sub is used for avoiding bass suck out around the sub's crossover point so that the sub can be better integrated with the main speakers. You will need to play a test CD that contains test tone. Or use the build-in tone generator of the processor if it has one. In either case, play the test tone that is closest to the crossover frequency and adjust the phase switch; whatever position sounds louder is the right setting.

The polarity switch change the phase of the input signal.

I am not familiar with your equipment but have usually found polarity switches to operate in the preamp section to alter the polarity (as described by Swampwalker) for the output of the preamp. Rowland, among others, used to use this to deal with amps or other devices which invert phase. I also don't know why manufacturers produce products that invert phase, but there may be a good reason I am unaware of. Subwoofers often have a phase switch (0= in-phase, 180= out-of-phase). This adjustment is the same reversal of polarity (+ and -) as seen on preamps but used strictly at the subwoofer to integrate with the main speakers as Sidssp outlined. It is no different than if you just switched your cables at the sub. Proper setting for this will be a function of sub placement relative to the main speakers and Sidssp's method is the way to determine what works in your application. You want the two bass sources to be as in phase as possible and this will become evident as the amplitude increases around the crossover point. If you can't hear which setting is louder at that frequency area, use a test CD, and if necessary, a Radio Shack analog DB meter. I recommend the test CD by Rives which compensates for the inaccuracies in the meter and may help you place your woofer for the flattest response in your room. Room placement is extremely critical for subs, despite what some advertisers claim. Random placement and reliance strictly on volume and phase adjustments rarely leads to satisfactory bass integration. I hope this helps.

The polarity switch inverts the polarity of the woofer 180 degrees, while a phase control might give you continuously variable phase change (my Paradigm allows change from 0 to 180 degrees). To do this simply, with both the satellites and sub playing a recording with a consistant low bass instrument, turn the phase control until you get the most bass. Then you can play with the polarity invert feature to see which position sounds more natural to you. You could also do this with a test disc and a meter as suggested above, but it's probably not necessary. Regardless of the amount of control you have, there is no substitute for proper placement of the woofer in the room... Move it around and leave it where it sounds the best. Sometimes moving the woofer a matter of inches makes for profound audible improvements. I usually position the satellites for best bass first and subsequently position the sub.