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I have a question about subwoofer phase. I bought a new sub and it has phase 180 and 0. What exactly is phase on a subwoofer, and what should I set this to?

The phase switch affects the soundwave the subwoofer produces -- when you flip the switch, the sound wave becomes inverted. For example, instead of moving in out in out, the speaker come will move out in out in.

The switch is useful to help the sub blend well with your mains. If you think your sub isn't blending well with your main speakers, try flipping the switch to see if it helps.

Chances are you have the sub connected to a receiver that handles the crossover, so the phase switch might not have a noticeable effect.

I hope I explained things at least semi-clearly.

Jason-

The sub and satellites work together - if they are in phase. If they are out of phase the speakers produce a compression wave (move forward) and the sub produces a rarefaction (moves backward). If this occurs the waves cancel each other out (like matter and antimatter) and the bass can be severly diminshed. (Sorry no warp speed produced!)

Basically, you should set the switch in the position where you hear the most bass.

Fascinating. I have crossover handled by my reciever (Denon AVR-1802), and have found that the 180-degree phase control on my sub (Adire Rava) has no measurable effect, either to the ear or to a RatShack SPL meter. I had just about decided that the phase control was broken! Now I'm curious: Why does having the receiver handle the crossover reduce the impact of the sub's phase control? Thanks!

Hi Robdarst,

It really has nothing to do with using the receiver's crossover or the sub's crossover. With all the standing waves, cancellations and reinforcements that occur with deep bass in every room, which are also affected by the sub's location, your location, and the dimensions of a given room, in lots of cases you won't hear any difference at all when you move the phase switch. Just moving your chair a couple of feet (or the subwoofer) will likely introduce far greater audible differences in bass response than toggling the phase switch.