Rew Alignment Tool Approach Help

[Altsouza]

Hello @jtalden

Knowing of your immense knowledge in Rew, I ask for your help in using the Alignment Tool function.

I recently bought a Minidsp SHD studio. Initially I'm not going to use Dirac, I'm only focusing on Mains Sub integration using only the Minidsp Plugin.

The SHD Studio is a Dirac and MiniDsp Plugin 2.2 processor without DAC. I use it with two Dacs, one for the Main Speakers and One for the two Subs.
After this step I will focus on Dirac.

Looking at several posts on this forum, including several of your recommendations, I made a list that I think is the correct sequence to make this integration.
My system consists of:
MiniDsp Studio Out 1/2 > Dac (AES) > Power Amp Parasound A21 > Kef R300
MiniDsp Studio Out 3/4 > Dac (spdif) > 2 SVS Subs
The Sub1 is located behind the R main speaker (Front Right corner) - I will name it front sub
The Sub 2 is located in diagonal, in rear left corner, 2/5 from rear wall, near the LP. I will name it rear sub.
The Front Speakers are located 1/5 from front wall.
The Room is 3x5 meters and LP is 1/5 from rear wall.
I Can Not move the Subs or Mains or furniture because of WAF (Wife....)
I decided for a 60hz XO because I think i need to use more of the Kefs (maybe is a wrong thinking)

The Steps:
1. Measurement - Individual Kefs and Subs with Time reference (four individual measurements)
2. Time Align the Subs using Align Tool , using slider for the delay for rear sub (it was 3.5ms delay)
3. Aplied delay on MiniDsp and measure the Both subs together
4. Aplied Eq for both subs together in Minidsp - to smooth the subs
5. Trace Aritimetic both Kef Speakers A+B (Just clicked the trace buton and Created the A+B) (I do not know to use this fuction, just followed from other posts)
6. Time Align Kef (A+B) with Sub1+Sub2 (Gave a 14.15ms delay for the subs), using Align from XO cursor.
7. Aplied a 14.15 delay for the front sub and for the rear sub I added 3.5 from above , so 14.15+3.5=17.65ms to rear sub.

I attached the Measurements.

Any help is welcome.

Thanks
Antonio

 

[Altsouza]

Hi @jtalden
Here are photos of my room just for reference. All Walls are concrete with Dry wall on Ceiling and dry wall panel on right wall and Large Wood door on left side. In the last renovation of my apartment I did some acoustic treatments without much discretion. I put a perforated acoustic panel on the front wall (about 15cm from the front with glass wool inside). On the ceiling I put this "a kind of enlarged sew saw" (four panes) ceiling with wool fiber inside. There's this huge sofa that my wife gave me as a gift, which I can't move (waf).

 

[jtalden]

The Steps:
1. Measurement - Individual Kefs and Subs with Time reference (four individual measurements)
2. Time Align the Subs using Align Tool , using slider for the delay for rear sub (it was 3.5ms delay)
3. Aplied delay on MiniDsp and measure the Both subs together
4. Aplied Eq for both subs together in Minidsp - to smooth the subs
5. Trace Aritimetic both Kef Speakers A+B (Just clicked the trace buton and Created the A+B) (I do not know to use this fuction, just followed from other posts)
6. Time Align Kef (A+B) with Sub1+Sub2 (Gave a 14.15ms delay for the subs), using Align from XO cursor.
7. Aplied a 14.15 delay for the front sub and for the rear sub I added 3.5 from above , so 14.15+3.5=17.65ms to rear sub.

This basically sounds like a correct approach. I take it that you made the changes and remeasured as you applied each change. Rather than trying to follow this in detail, I just took the first 4 measurements and worked through the analysis using them. I did retain your last measurement as #5, but deleted the rest of them before starting my analysis. I compared your final SPL result to mine as shown below. My result does not include the impact of Dirac EQ so the bass range is not directly comparable, but it appears be a more favorable timing. I also attach my working file for your information.

I found the most favorable SW changes from the initial starting setting as:
Left SW: invert its polarity and also increase its delay by 7 ms
Right SW: reduce its delay by 2.5 ms. [If you started at 0 ms delay that is a problem unless the mains can be delayed. I did not check to see the impact of leaving this at the current setting, but it is likely to be close enough to work well.]

[/QUOTE]

 

[Altsouza]

This basically sounds like a correct approach. I take it that you made the changes and remeasured as you applied each change. Rather than trying to follow this in detail, I just took the first 4 measurements and worked through the analysis using them. I did retain your last measurement as #5, but deleted the rest of them before starting my analysis. I compared your final SPL result to mine as shown below. My result does not include the impact of Dirac EQ so the bass range is not directly comparable, but it appears be a more favorable timing. I also attach my working file for your information.

I found the most favorable SW changes from the initial starting setting as:
Left SW: invert its polarity and also increase its delay by 7 ms
Right SW: reduce its delay by 2.5 ms. [If you started at 0 ms delay that is a problem unless the mains can be delayed. I did not check to see the impact of leaving this at the current setting, but it is likely to be close enough to work well.]

View attachment 45999

[/QUOTE]
Hi @jtalden ,
Thank you for your reply.
I will analise you recommendations and get back asap.
Thanks again
Antonio

 

[Altsouza]

Hi,
So I need to increase to 9.5 ms to rear sub (also invert) in the inter-sub alignment, and apply a 2.5ms at mains (Yes, I can delay the mains) in the final sub x mains alignment.
Is that correect?
thanks

 

[jtalden]

That is correct.
Please post the 4 measurements again after making the delay changes and applying Dirac. I would like to see the results.

 

[Altsouza]

Ok. I will do Dirac maybe tomorrow, as I need to study it a little more.
Thanks
Antônio

 

[Altsouza]

Hi @jtalden
Here are the Dirac photos. I am new to Dirac, so I sent screen photos and also Rew final measurament including Dirac.
Dirac don't change minidsp plugin setings, so all delays and Sub peq we talked before remains.
If you want some more info please ask.
Thanks

 

[jtalden]

Very confusing! I gave the wrong instruction for changing the timing in Post-3. I mixed up the changes to front and rear SWs.

This time I started over again using the first 4 measurement in Post-8 so use those current delay settings and make the changes noted here:

• Front SW: Reduce its delay by 2ms and reverse its polarity
• Rear SW: Increase its delay by 9 ms

I don't know how much this will impact the SPL as Dirac may make up and difference. I do know the relative timing between the SWs and mains will be much better.

Attached is my mdat.

 

[Altsouza]

Very confusing! I gave the wrong instruction for changing the timing in Post-3. I mixed up the changes to front and rear SWs.

This time I started over again using the first 4 measurement in Post-8 so use those current delay settings and make the changes noted here:

• Front SW: Reduce its delay by 2ms and reverse its polarity
• Rear SW: Increase its delay by 9 ms

I don't know how much this will impact the SPL as Dirac may make up and difference. I do know the relative timing between the SWs and mains will be much better.

Attached is my mdat.

I am confused. Can you give me the Actual Delays for each sub.
Thanks
Antonio

 

[jtalden]

Yes. What were the delay settings used for the measurements in Post-9?