MSO- Multi Sub Optimizer Beginners Thread

[NorCalRP]

Should I try transferring the information from MSO into MiniDSP without using the biquad information? Am I doing something terribly wrong by exporting that biquad info directly into MiniDSP- should REW be used as some sort of a middle link in the chain?

 

[Pogre]

3) This is nitpicking I know, but it's become a convention of sorts on the forums to adjust the y-axis range of graphs to get 5 dB/div. Using 10 dB/div or larger tends to hide problems.

I agree, and meant to change that. Here's one that is.

Little bit of a house curve in that one. No smoothing.

 

[NorCalRP]

I agree, and meant to change that. Here's one that is.

View attachment 31519

Little bit of a house curve in that one. No smoothing.

I'd be thrilled if my curve looked like that.

 

[Pogre]

I'd be thrilled if my curve looked like that.

I am, lol. That's after generating some filters from my spl sweeps in REW. No manual EQ. What you're attempting to do seems to me to cover a lot more bases than just spl. I'm keeping an eye on this thread and watching your progress. As it is now, I think it sounds awesome, but I learned early on that "awesome" is pretty subjective. Until I've heard better, my perception of awesome could be off. I thought I had awesome with a pair if 10" Klipsch subs until I heard better.

 

[NorCalRP]

I am, lol. That's after generating some filters from my spl sweeps in REW. No manual EQ. What you're attempting to do seems to me to cover a lot more bases than just spl. I'm keeping an eye on this thread and watching your progress. As it is now, I think it sounds awesome, but I learned early on that "awesome" is pretty subjective. Until I've heard better, my perception of awesome could be off. I thought I had awesome with a pair if 10" Klipsch subs until I heard better.

Yeah, I'm not going any deeper than the SPL sweeps either. I did read somewhere to create a filter in REW with the speakers set to none. It gave me a ruler flat target curve. I'm interested to see how it might alter my response. What I'm not sure of is how I properly import it into my HD. Do I apply it to the PEQ on the input side so as to keep the biquad info in the PEQ's on the output side, or do I create a target curve for each sub from the average of all 3 seats then replace the biquad info on the output side for each subs peq?

Definitely not done with MSO- I've seen results and believe the methodology to be superior to mainstream bass management platforms such as Dirac, ARC, and the other big 3. It's fun to learn by tinkering though.

 

[NorCalRP]

@andy_c Tonight I'll run a calibration again and snap pics of the tree as I add things to it. Hopefully you can give me some insight about what I'm doing wrong

 

[NorCalRP]

I took a new set of measurements. What I had not done before was check the levels using the tone generator before every single measurement. It makes sense to me now that so many of my spl levels on my sweeps were so far off. Hoping this will play a role in improving things.

 

[NorCalRP]

I missed this the first time. If you do a measurement in REW, then export it as an FRD file, then import it into MSO using File, Import Plot-Only Measurement, there is absolutely, positively, no f'ing way that MSO will show a different result than REW. Anyone making such a claim is wrong.

If anyone "made the claim", that'd be me. I'm a total noob. There's an excellent chance I'm doing the wrong things, saying the wrong things, etc. I distinctly remember reading about the steep learning curve

 

[NorCalRP]

This is before optimization

This is after.

Did I make a mistake during measurements by adjusting the level on the mic at each location, for each measurement (9 adjustments)

 

[JStewart]

Did I make a mistake during measurements by adjusting the level on the mic at each location, for each measurement (9 adjustments)

Answer is yes. Changing the volume of a sub (or it’s measured volume) changes the combined response. Unless the change was equal for each sub at every listening position.
To state the obvious, something else is still not right for the before and after to be so nearly the same.
Wonder where Andy got to.

 

[NorCalRP]

Answer is yes. Changing the volume of a sub (or it’s measured volume) changes the combined response. Unless the change was equal for each sub at every listening position.
To state the obvious, something else is still not right for the before and after to be so nearly the same.
Wonder where Andy got to.

I set each sub, at each location, each measurements, to 75dB.

Great question regarding Andy

 

[Pogre]

Great question regarding Andy

His lack of support all of a sudden is a little bothersome. At this point I'm not very inspired to try MSO...

 

[NorCalRP]

His lack of support all of a sudden is a little bothersome. At this point I'm not very inspired to try MSO...

I just upgraded my MiniDSP to the DDRC-24 with Dirac 2.0. I'm interested to see how the results will compare to XT32

 

[JStewart]

I set each sub, at each location, each measurements, to 75dB.

That means you set the volume control on each sub so it was 75dB at the mlp AND THEN TOOK ALL MEASUREMENTS AFTER?
If yes then all is well.

If you can attach your rew measurements and mso project file I’ll be happy to have look while we wait for Andy to return.

 

[Tony Barrett]

Hi. Thanks for this thread. I’ve run MSO with 10 PEQ filters, following the instructions in minidsp’s Application Note on MSO and the DDRC-88A. When I import the biquad text files to a 2x4HD (which I use for the subs). The PEQ values are greater than minus 20db and go off the scale of the PEQ graph in the minidsp plugin. The PEQ values are maximum minus 15db in MSO. Anyone have any idea what’s going on? Merry Christmas!

 

[JStewart]

Hi. Thanks for this thread. I’ve run MSO with 10 PEQ filters, following the instructions in minidsp’s Application Note on MSO and the DDRC-88A. When I import the biquad text files to a 2x4HD (which I use for the subs). The PEQ values are greater than minus 20db and go off the scale of the PEQ graph in the minidsp plugin. The PEQ values are maximum minus 15db in MSO. Anyone have any idea what’s going on? Merry Christmas!

You're saying the filter doesn't look the same on the MiniDSP as it does in MSO? Might be because the sample rates of the two MiniDSP devices are different. 2x4HD uses 96k. DDRC-88A 48k. I'm not home to look at MSO, but there is a place to select the hardware being used or the sample rate IIRC its under Application options.

 

[Tony Barrett]

You're saying the filter doesn't look the same on the MiniDSP as it does in MSO? Might be because the sample rates of the two MiniDSP devices are different. 2x4HD uses 96k. DDRC-88A 48k. I'm not home to look at MSO, but there is a place to select the hardware being used or the sample rate IIRC its under Application options.

Hi. Thanks for this suggestion. I’ve previously tried switching to 96k and reexporting the biquad text files and importing to the 2x4HD. Didn’t seem to make any difference. I may try to set a lower maximum/minimum gain on the PEQ filters and rerun optimisation and see how that works. The filters look the right shape on import but the cut is in excess of 20db on the minidsp, compared with -15db in MSO. I used all 10 PEQs available, which may also be too many. Not sure. Thanks again.

 

[Wellz]

Also, in in MSO's Tools, Application Options, choose "Hardware" and ensure that the sample rate is what the 2x4 HD uses, which is 96 kHz. If this was incorrect, you'll need to re-export the biquad files from MSO and re-import them into the miniDSP software. The maximum biquad count for input and output biquads should be set to 10.

This part took me for a loop as the say! I set the rate in REW to 96 kHz but then didn't change the MSO Hardware from 48 kHz to 96 as I should have. I ran MSO and the results look great but when I uploaded the Biquads into my new 2x4HD (which is set at 96kHz) the results looked horrible. Luckly I remembered reading this peace in this thread, and now I'm correcting the problem by changing the hardware info in MSO and rerunning the Configuration Optimization.
I do have another question about this... In REW under Preferences there is a Sample Rate drop down window. Should that one be set to the rate that the UMIK-1 uses, or the rate that the 2x4HD uses?

Thanks for the awesome program, Andy!

 

[alexf40]

Hi all, thanking you all in advance for any advice and comments on the below, and look forward to being a part of the community moving forwards.

I've spent days reading about how to setup twin subs with REW and use the time alignment tool and never managed to get it working properly. I then read about MSO and after reading the tutorial realised this was a much better option for setting up my subs.

However after getting amazing before and after results with the graphs, when I loaded the setttings to my MiniDSP and re-performed a sweep in REW I discovered that the results were nothing like the prediction.

On further reading it looks like I have used the wrong timing references with REW. I used the loopback timing function and not acoustic as mentioned here https://www.andyc.diy-audio-engineering.org/mso/html/measuring.html (I'm using a USB Umik-1)

However after reading this several times I'm really unsure now on how to actually perform the measurements for my twin sub 7.1 system.

The guide it links to no longer exists. Does anyone have a dummies guide on how to do it? E.g which speakers, which sweep frequency range etc.

Also if anyone could clarify the optimisation frequency ranges for MSO that'd be great, as after reading the tutorial I'm just using the default settings, as I'm still confused on this. Also the tutorial settings can't be used as they are outside the allowable ranges in MSO.

Thanks again
Alex

 

[Tony Barrett]

Hi Alex

Did You look through these?

Multi-SUB Optimizer + DDRC-88

miniDSP is a leading manufacturer of Digital Audio Signal Processors for the HomeTheater, Hifi, headphone and Automotive market. Join our large community of Audiophiles, Engineers and DIYers using our innovative products.

www.minidsp.com

2.2 Sub integration + MSO

miniDSP is a leading manufacturer of Digital Audio Signal Processors for the HomeTheater, Hifi, headphone and Automotive market. Join our large community of Audiophiles, Engineers and DIYers using our innovative products.

www.minidsp.com

I used the first as a dummies guide to how to run a sub only optimisation. It’s for minidsp‘s DDRC-88a but should work more or less the same with other units. Just be careful to use the correct hardware setting. The 88a uses 48 kHz setting but you’ll need to set it at 96 kHz if you’re using the 2x4HD unit (see the comment in this thread just above yours). I’m not sure about the regular 2x4 unit, pretty sure that’s 48 kHz but the specs will be on minidsp’ s website.

You want to run a sweep that covers all of the subs’ useful range. I did 10hz to 300hz, I think, mainly because I seem to have some huge room gain below 20hz, though maybe it’s a measurement artefact. Need to be a long enough sweep. I set to 2m length in REW with no smoothing. The minidsp guides have some details. I did an optimisation range of 20hz to 120hz as recommended by minidsp. That covers the sub’s useful range through the crossover.

if you’re doing a subs + mains optimisation with MSO, the second linked guide may be more useful. I haven’t used it yet but plan to in another room.

cheers,
Tony