Great video, thank you! Let's also remember that time aligning to the on-axis A pos, or Merlings suggestion will mean delaying your main LR a bit since most stages are wider than they are tall. Delaying your LR has all sorts of effects on how your directs sound works with the reinforced sound, that may or may not be much more noticable the exact phase alignment is at your x-over freq.
So when doing this in the field, and setting your crossover filters & levels at this position, would you suggest doing the measurements with only the top-left & sub, but then where you'd normally assume 6dB of summation, try to hit a crossover point -9dB down instead (and then confirm with both tops + sub on)? Or would you initially capture a trace with both mains on and try to set the crossover and align the sub to that?
Hi Mashzmash. Short answer, yes your first method sounds good. Longer answer, I would not try to set crossover filters in the field. I would set them ahead of time so I could put them on the ground and get high quality quasi-anechoic data to work with. If I was forced to set filters in the field, I would validate them with with very close measurements (~1-2m). When it comes to which sources to turn on during alignment, the official answer is that everything should be on, but almost no one does that because it makes the data difficult to read. These topics are covered here: www.sounddesignlive.com/the-complete-guide-to-measurement-microphone-placement-for-subwoofer-alignment/
Hey Robin, in general, yes. For a line, the acoustic center will be the center. For an arc, the acoustic center will be in the center, but somewhere behind the array, so it will appear to appear to come from somewhere along the array depending on where you listen/measure, so I usually just estimate the center to keep it simple. This may help www.sounddesignlive.com/the-complete-guide-to-measurement-microphone-placement-for-subwoofer-alignment/
1000% agree,, but when I have to I put them center I place them behind the stage. I find it sounds tighter when phase align the hang after the subs complete a cycle @ cross in the z plane
