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Unexpected results when time aligning subwoofers

DonH56

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If you have no dips, or minimal, then you're there.

Again, crossovers are not brick walls that drop instantly to zero on either side, so the subs will affect the mains for at least an octave above the crossover, and the mains will affect the subs for an octave or so below (how much impact, and how far up/down in frequency, depends upon the crossover slopes).
 

Jdunk54nl

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The subs did not impact the high frequency. They don't play that high up so can't impact that.

There are two things that could cause that. When you adjusted your subs and made your left front the farthest distance speaker, its delay is now 0ms and the right front is some other number based on that. This might have been a 0.1ms difference which would cause some shifts at higher frequencies.

Or the more likely reason, getting two identical responses with a sweep in a single spot is VERY hard to do.
 
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CBM

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The subs did not impact the high frequency. They don't play that high up so can't impact that.

There are two things that could cause that. When you adjusted your subs and made your left front the farthest distance speaker, its delay is now 0ms and the right front is some other number based on that. This might have been a 0.1ms difference which would cause some shifts at higher frequencies.

Or the more likely reason, getting two identical responses with a sweep in a single spot is VERY hard to do.
I was surprised that the bass changed the high frequencies too. When I changed the distance values of sub 2 alone
subs 17 and 9.2 ft vs 17 and 13.9.jpg
20 - 20,000 Log.jpg
, the high frequencies were unaffected. It was when I changed the distance values of both subs equally that the higher frequencies changed.
 

Jdunk54nl

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IF you get the same response every time via sweep and mic in one spot, then the only other possibility is that your speakers now have a different time delay relative to each other.

Like I said before, the Left front is now at 0ms delay since it is the farthest speaker.
So the difference in delay when they weren't the farthest to now must be different between the left front and right front. This would easily cause summing / cancellation differences at higher frequencies.

The means the relative phase between them must have change slightly due to the slight new delay differences between the left front and right front. I am sure you could get back to the original graph if you adjust the distance on the right front speaker.
 
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CBM

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I'm going to try that. You have been very helpful in my understanding of this issue. Thank you.
 
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