For a brand new Subwoofer guy never having one before what does “Low Pass” and “Phase” mean? On my new PSW404 Polk Audio Sub there is a turning knob for Low Pass that goes from 60 to 125 with 90 being the center. And then there is a two position toggle switch that switches from 0 to 180 no in-between it’s just either or. Then last but not least there is a auto on auto off switch, is it best to just leave it on the auto position?

Set the Low pass to 180 on the sub and go to your receiver and manage it from there. There should be some kind of bass management/ speaker config. That is what will ultimately tell the sub to come on, try to set the LFE (low pass) to around 80 to 100hz. If nothing else make sure your speakers are set to "small" and that will send more bass to your sub.



Phase as I understand it switches the polarity of the speaker. My understanding is that's good for situations where other speakers are canceling each other out thus switching the phase produces a signal that doesn't cancel out.


Hope that helped.

Pasted right out of the manual:

AC POWER CONNECTION AND AUTO ON/OFF (FIGURES 10,11 & 12)
These PSW series subwoofers feature auto on/off circuitry, marked “auto” on the power switch, that automatically turns your subwoofer on when it senses a program signal. When no signal is present, the circuit turns the subwoofer off after a few minutes. If you are concerned about the brief delay between when the music starts and when the subwoofer turns on, simply leave your subwoofer in the “on” position. When the power switch is set to “OFF” (PSW303 or PSW404) or “STANDBY” (PSW505) it consumes a low amount of power. If this is a concern, you may want to leave your PSW system unplugged during extended periods of non use, such as during a vacation.



Phase Switch—Have someone switch between the two settings while you sit in your favorite listening position. Use music with good bass and a deep male vocal. When you hear the best balance of deep bass and natural lower octaves of the male voice, you have achieved optimum phase tuning.


HOOK-UP METHOD #2 (FIGURE 8)
This method can be used with electronics that include a “SUB OUT” feature (Figure 8). It is not recommended for use with compact sub/sat systems. Connect a single RCA cable from the “SUB OUT” of your electronics to the LFE input of the subwoofer. This input bypasses the subwoofer’s variable low pass filter and relies on the filter built into your electronics. This is what you want. No need to worry about the crossover setting on the sub.

If your “SUB OUT” is an unfiltered signal (check your owner’s manual), use either left or right “Line Level Input,” to use the low pass crossover in the subwoofer. When using method #2, it is necessary to adjust the settings of your electronics as follows: Front speakers = large or small depending on their output capabilities; Subwoofer = “ON.”

Most in this forum, including me, would disagree with some of the Polk recommended set up instructions. They assume the crossover circuitry in the sub is better than in your receiver. The text in red are my words.