[miklorsmith]

I have dual subs and infinite adjustment for phase.  I've been playing with it and have found some settings that definitely seem better than stock.  It's just ear-tuning though, nothing precise.

I have REW set up and know how it works, at least as far as frequency response testing goes.

Tips?

[WerTicus]

wherever the spl is loudest at the xover frequency is where they are in phase at the position of the mic.

[miklorsmith]

So, a pink noise signal with significant overlap should be loudest when phase is correct?  I wonder if my SPL meter is sensitive enough . . .

I should be able to get close with that, but is there some kind of impulse test that will get more or less exact?

[miklorsmith]

It seems with REW's "Impulse" measurement this could be done but the tutorial says basically whenever the system "hears" first sound, "Time 0" begins.  I guess I could try running this to see whether two distinct peaks are present.

If so, I should be able to experiment with different phase settings until the peaks line up?  Hmmm, that might not work since the sub might be a full cycle behind when everything's perfect which wouldn't look right on such a graph.

Considering REW's home theater roots, it seems there should be a specific function to do this.

There are lots of subwooferers 'round here, what do you guys do?

[miklorsmith]

A very nice fellow forwarded this along:

http://forums.avguide.com/viewtopic.php?p=613&

It seems the perfect solution.  I think I can use Audacity to generate exactly the tone I need, then it's pretty straightforward.  One speaker at a time I'll use the SPL meter to set the same volume between the main and subwoofer individually.  This should make the "maximum cancellation" very easy to hear and measure.  Then I'll do the other speaker/sub and hopefully the combined result will agree.