REW EQ Filters on Two Subs

408Revo

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Hi, first off thanks everyone for all the help everyone has provided me, greatly appreciate it. It’s been a couple months since I fell into this rabbit hole and the more I learn the more amaze I am with using REW.

I’m currently working on aligning two subs using a mini DSP. I’ve notice that when adding my second sub it hurts my 1st sub at certain frequencies as the dbs go down and at other frequencies it does the opposite, dbs go up.

So what I’ve done is inserted negative filters on my second sub at those frequencies where the dbs drop on my 1st sub and notice a great improvement as the negative effect starts to disappear. Doesn’t go away completely but does help.

Is this correct what I’m doing? Is it ok to add filters to a second sub when trying to add it to the first?
 

3dbinCanada

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I'm no expert in REW but I have used it to control 3 subs in the great room system and two subs in the basement system. I used REW to generate the filter coefficients after I played with the delay settings and inverted the phase on one of my subs.

Here are the delay settings
Sub1: 10ms Inverted
Sub2: 1.45ms
Sub3: 3ms

Here's what REW predicted it could do for me. That's the red line supper imposed on the target curve (blue trace). The other red trace is the combined sub response with delays and inversions Pre REW EQ
Prediction Traces.jpg


The next graph shows the actual response of the combined subs after REW EQ them and the filter coefficients downloaded into a miniDSP 2x4HD.

Combined Sub Response PreEQ vs Post Eq.jpg


I used this link to get me started..

 

Gerry Iaria

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I'm no expert in REW but I have used it to control 3 subs in the great room system and two subs in the basement system. I used REW to generate the filter coefficients after I played with the delay settings and inverted the phase on one of my subs.

Here are the delay settings
Sub1: 10ms Inverted
Sub2: 1.45ms
Sub3: 3ms

Here's what REW predicted it could do for me. That's the red line supper imposed on the target curve (blue trace). The other red trace is the combined sub response with delays and inversions Pre REW EQ
View attachment 68793

The next graph shows the actual response of the combined subs after REW EQ them and the filter coefficients downloaded into a miniDSP 2x4HD.

View attachment 68794

I used this link to get me started..

looks very good to me :T
 
Joined
Mar 3, 2019
Messages
41
Hi, first off thanks everyone for all the help everyone has provided me, greatly appreciate it. It’s been a couple months since I fell into this rabbit hole and the more I learn the more amaze I am with using REW.

I’m currently working on aligning two subs using a mini DSP. I’ve notice that when adding my second sub it hurts my 1st sub at certain frequencies as the dbs go down and at other frequencies it does the opposite, dbs go up.

So what I’ve done is inserted negative filters on my second sub at those frequencies where the dbs drop on my 1st sub and notice a great improvement as the negative effect starts to disappear. Doesn’t go away completely but does help.

Is this correct what I’m doing? Is it ok to add filters to a second sub when trying to add it to the first?
Here is our new video on the topic:
 
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