VTF-2 phase question

[petertkim]

Is it ever ok to set the sub out of phase with the speakers? I assume that the phase setting that gives louder bass (0 deg in my case) is where the sub is in phase with the speakers. But sometimes I prefer the out of phase setting (180 deg) which seems to give tighter/less boomy bass. Is it always correct to set the sub in phase with the speakers, or is it more a matter of preference?
By the way, I am using VTF-2 with Axiom m22ti speakers connected at speaker level (my old Onkyo receiver does not have pre-amp or LFE options) - with crossover set at around 85 Hz.
Any input would be appreciated.

[Sasha_G]

I just call it the 180 degrees setting, and avoid referring to it as the "out of phase" setting. That is becaus having the phase of the subwoofer match the speakers depends on the location of all the speakers in your room, not the switch.

The bass heavy setting is in fact the more "IN PHASE" setting. However, the acoustics in your room must be causing a peak around the crossover region, and the out of phase setting of the swtich actually corrects for that peak by cancelling out the bass.

This is one of those zen-master subwoofer issues that is extremely hard to understand. However, my advice: use the setting that sounds better.

This is an excerpt from the upcoming STF and VTF manuals explaining the phase switch, for your interest:

Depending on the absolute phase of your main speakers and amplifier, and the distances of the subwoofer and the main speakers from the listening position, the bass in the crossover region may be smoother if you reverse the phase of the subwoofer. Switch the phase switch to 180 degrees to see if the bass sounds louder in the seating position. Play program materials with steady, consistent bass in the crossover
region (30 – 90 Hz). Filtered pink noise is best, but you may use music containing bass drums, double basses, bass guitar, etc.. The more bass-heavy setting is where the output of the subwoofer and the main speakers are most in phase. If the 180 degree position is louder, you will need to go back and adjust the volume level (Step 4). Otherwise, just switch the phase switch back to the original position.