REW Alignment tool - Guides or Manual?

[sm52]

regardless if it points up or down

To align the impulses, you should look at the peak of the impulse after the first rise of the graph from the zero level. Therefore, the highlight should start at one peak at the top of the zero level and end at the second peak at the top of the zero level.
If you have multiple acoustically synchronized measurements, you can figure out the offset time for any graph relative to any. If you want the distance (time of arrival of the signal) from the left speaker to the microphone to be equal to the distance (time of arrival of the signal) from the right speaker to the microphone, select the area from the positive peak of the impulse of the left speaker to the positive peak of the impulse of the right speaker. In the same way, act to align a sub with the left speakers. And a sub with the right speaker. It may turn out that the time (distance) to which you need to shift the left speaker for coordination with the subwoofer is not equal to the time (distance) to which you need to shift the right speaker for coordination with the sub.

 

[mmares056]

To align the impulses, you should look at the peak of the impulse after the first rise of the graph from the zero level. Therefore, the highlight should start at one peak at the top of the zero level and end at the second peak at the top of the zero level.
If you have multiple acoustically synchronized measurements, you can figure out the offset time for any graph relative to any. If you want the distance (time of arrival of the signal) from the left speaker to the microphone to be equal to the distance (time of arrival of the signal) from the right speaker to the microphone, select the area from the positive peak of the impulse of the left speaker to the positive peak of the impulse of the right speaker. In the same way, act to align a sub with the left speakers. And a sub with the right speaker. It may turn out that the time (distance) to which you need to shift the left speaker for coordination with the subwoofer is not equal to the time (distance) to which you need to shift the right speaker for coordination with the sub.

Thank you for the detailed explanation. This helps a lot. I also follow the Sub distance tweak methodology for my Sub to LCR integration in the crossover region with great success. Can you help answer the following questions that I still have. I use the FL as my reference to time align rest of speakers to it.

1) What does the "Ref" mark on impulse tab mean? Why is there? I'm sure John Mulcahy put it there for a reason.

2) What does the little dot at center of the impulse peak(Positive or Negative) mean?

3) Is it okay, is it still accurate to run sweeps with acoustic timing reference with the subs muted?

 

[sm52]

If you hover over Ref, the vertical line will indicate the time of the maximum peak. In your case, Ref indicates a negative peak. Align with positive peaks. It happens that Ref indicates a positive peak.
There are impuls values at points on your chart, but there are no impuls values between them. The impuls line is obtained after an approximation using data points. You can disable the drawing of points in the controls, remove the "show points when zoomed in" birdie.
As a reference, you can choose L, you can choose R, but not a sub. It is even better to connect a separate driver to the reference channel, which can play from 3 kHz to 12 kHz at least. For example, any tweeter. If your home theater has a center channel, you can make it a reference channel.
The procedure is as follows. You measure the full range of the speakers. L, R, sub relative to the same reference speaker. It is best to place the microphone at the same distance from L and R. Then the impulses L and R will coincide, and they will not have to be alignment. Then you find out the delay time L relative to the sub and R relative to the sub. Apply the same delay, the lesser of the two, to R and L. Or the middle of the two. Again measure each of the three speakers separately with delays. Then see at what frequency it is best to make a crossover point (slice) between L and sub, R and sub. And what a slope of the filter.
Usually, R and L are not equally consistent with the sub. If L is doing well with the sub, then R is not doing well, or vice versa. Therefore, it takes many attempts to change the crossover frequency to do this.

 

[mmares056]

If you hover over Ref, the vertical line will indicate the time of the maximum peak. In your case, Ref indicates a negative peak. Align with positive peaks. It happens that Ref indicates a positive peak.
There are impuls values at points on your chart, but there are no impuls values between them. The impuls line is obtained after an approximation using data points. You can disable the drawing of points in the controls, remove the "show points when zoomed in" birdie.
As a reference, you can choose L, you can choose R, but not a sub. It is even better to connect a separate driver to the reference channel, which can play from 3 kHz to 12 kHz at least. For example, any tweeter. If your home theater has a center channel, you can make it a reference channel.
The procedure is as follows. You measure the full range of the speakers. L, R, sub relative to the same reference speaker. It is best to place the microphone at the same distance from L and R. Then the impulses L and R will coincide, and they will not have to be alignment. Then you find out the delay time L relative to the sub and R relative to the sub. Apply the same delay, the lesser of the two, to R and L. Or the middle of the two. Again measure each of the three speakers separately with delays. Then see at what frequency it is best to make a crossover point (slice) between L and sub, R and sub. And what a slope of the filter.
Usually, R and L are not equally consistent with the sub. If L is doing well with the sub, then R is not doing well, or vice versa. Therefore, it takes many attempts to change the crossover frequency to do this.

Okay and just to clarify my example with the R speaker on the screenshot, align downward peak where Ref vertical line is to reference L which time of maximum peak for L happens to be a positive peak. Thanks again. Your help is greatly appreciated.

 

[sm52]

just to clarify my example with the R speaker on the screenshot, align downward peak where Ref vertical line is to reference L which time of maximum peak for L happens to be a positive peak.

I did not quite understand. You should work for some time in REW, each time listening to what happened. If the final result does not suit you, publish the MDAT file with measurements with acoustic synchronization of all your speakers. I will see which delays are better suited.

 

[mmares056]

I did not quite understand. You should work for some time in REW, each time listening to what happened. If the final result does not suit you, publish the MDAT file with measurements with acoustic synchronization of all your speakers. I will see which delays are better suited.

Sorry for not explaining things as clear. Here is my mdat file for my alignment project post EQ. I took measurements for the same speaker but at different distance values to compare and select the distance value for the most precise timing. The number after the channel abbreviation represents the distance(ft) at which the measurement was taken. Thank you in advance for all your help.

 

[sm52]

I looked. For L, R, you need to install a delay of 4.83 m, or 15 ft 10.2 In. As for the side and rear, we will look at them later. At the same time, there is a small problem on the 35-60 Herz section, so it’s better to try 3 or 4 order of the filters. At a frequency of 75 Hz.
This is the average delay figure for R and L. With this delay, L + sub is looked almost well. R + sub looks bad.
At the back, after about 5 m from the microphone, a very strong reflection is created from the sub. It will interfere, but you cannot remove it.
The microphone was installed approximately 7 cm closer to L than to R. But mathematics REW solves it.
Install, if possible, coolest slope of the filters, delay of 4.83 m, and make one measurement for each of all the speakers.

 

[mmares056]

I looked. For L, R, you need to install a delay of 4.83 m, or 15 ft 10.2 In. As for the side and rear, we will look at them later. At the same time, there is a small problem on the 35-60 Herz section, so it’s better to try 3 or 4 order of the filters. At a frequency of 75 Hz.
This is the average delay figure for R and L. With this delay, L + sub is looked almost well. R + sub looks bad.
At the back, after about 5 m from the microphone, a very strong reflection is created from the sub. It will interfere, but you cannot remove it.
The microphone was installed approximately 7 cm closer to L than to R. But mathematics REW solves it.
Install, if possible, coolest slope of the filters, delay of 4.83 m, and make one measurement for each of all the speakers.

Thank you for taking a look at my mdat file. I find this(Screenshot attached) to look like the most precise/closest alignment for my speakers with L set as my timing reference. Does the alignment look good to you?

 

[sm52]

TFL can be moved to the right by 3.5 cm, and C to the left by 3.5 cm. If the delays do not allow the speaker to be repositioned by a very small distance, it is possible to physically move the speaker. The peak of the sub"s impuls will be slightly shifted from the rest.
It seems that on your screenshot of the measurement is not separately speakers and a sub, but each speaker along with a sub. This is how it should be. But this is not the best option.