Question about dual sub, rew and allignment

[Pieter1267]

Sorry, no time yet. In short:
View attachment 421387
Which is what I wrote about earlier)
This may sound good:
View attachment 421388
View attachment 421389

But youve kind of lost me since i havent touched the waterfall and other graphs yet. What am I looking at?

Here is another measurement graph on higher SPL that shows indeed, the lower SPL with both - problem, is fixed. Red line is both. Orange line is R sub. Purple line is L sub (the one that was faulty wired).

I now seem to have a big null to fix, but we can do that with some room treatment and possible, moving round a bit.

 

[Flaesh]

It is not generally accepted in society to show a linear abscissa scale, use a logarithmic one.

a big null to fix

What, 77 Hz? This is small deep, with 1/3 smoothing it doesn't even exist))
You may add a few dB for 10-30 hertz if you want, and subwoofers can.
Your LRs operate from approximately 80 hertz. Integration of LR and subs is the next step.

 

[Keith_W]

I assured you in my previous post that once you invert the polarity of one sub, it will look similar to the tracing predicted by REW. So here is proof.

Light blue: L + R sub together, polarity un-inverted.
Dark yellow: L sub polarity inverted in REW and added to the right sub - predicted frequency response.
Green: actual measurement of L + R sub together with polarity of one sub inverted.

Trust us, we are old hands at this As @Flaesh says, the next step is to integrate your subs with your speakers. I can't see any speakers in the photo that you posted here unless we are looking at the little bookshelf things sitting on the computer desk. There are several options. You could try a manual correction. Or you could try MSO. I would recommend MSO, it automates what is normally a very difficult task.

 

[Pieter1267]

I assured you in my previous post that once you invert the polarity of one sub, it will look similar to the tracing predicted by REW. So here is proof.

View attachment 421494
Light blue: L + R sub together, polarity un-inverted.
Dark yellow: L sub polarity inverted in REW and added to the right sub - predicted frequency response.
Green: actual measurement of L + R sub together with polarity of one sub inverted.

Trust us, we are old hands at this As @Flaesh says, the next step is to integrate your subs with your speakers. I can't see any speakers in the photo that you posted here unless we are looking at the little bookshelf things sitting on the computer desk. There are several options. You could try a manual correction. Or you could try MSO. I would recommend MSO, it automates what is normally a very difficult task.

But I actually took the first suggestion and tested inverted. Then I did it again. Then it produced very strange charts, wich made me wonder next to your valid points, wether Windows is taking the mickey. And so it proofed. I am sure I clicked ''invert', I see it highlighted and nothing happens?

Anyway, now I have cleaned up Windows, know a lot more about REW and because of you guys we fixed the lower spl problem. Maybe I shouldv been clearer indeed both are DIY subs so it wasnt that obvious to check.

I currently have a temporary set of mb quart 390 mains, wich will be replaced in the near future. The REW readings are all over the place in the lower regions but they do give some good SPL and very clear highs. Got them for very little money and for now, testing, they are okay.

I had some fun today though, getting them to work with the subs. Per @Flaesh I upped the 10-30hz regiona bit, lowered a small area at 45hz and between 67 and 73. It looks the spl goes down a bit after 90 so i decided to cross at 80-ish (83). I made a 65hz cross preset for reference and just to see/hear any difference. I kinda like the 83hz wich feels full. The 65hz gives bas a bit more direction from the mains. Its very little though.

For the mains I decided to let Autorew have some fun. the mb quarts look a bit wild at lower frequencies. The autorew seems to have tamed some, except some huge spike at 160hz.



Its not yet finished and I need to learn more about how to measure the full range speakers and how to read the charts. At im testing 2 configs, on on 83hz crossover and one at 65hz. For now ill dial down all the measuring and spend my time on other things, also I just want to play a few days some music to get a better idea and feel. That said, mso is on the menu for next week. Again, thanks so much for your help and insights.

For anyone interested in included the .mdat file what I did the last few hours.

 

[Pieter1267]

My wife decided to put up some curtains and this helped get rid of a lot of echo/reverb. I watched a lot of MSO tutorial, untill after an hour the guy stated ''oh, if you only use one main listening position, you dont need MSO''. Thank you!

So i went back to scratch, completed new clean measurements of the subs and the main speakers. Then went and made a few PEQs, both manually and by autorew. I decided to leave as much boost out of it. In the end the manual peq setting for both subs showed the flattest line.

This is both subs before (blue) and the result (brown)

The mildest autorew file was the best for the mains. Then I tested and levelled the output of both. Created 3 crossover pre-sets; 60, 80 and 100 hz.

Started playing Prince controversy, since despite his rep his productions werent the best with low bass. Then The Cure A Forest. Then Jimi Hendrix Spanish Castle Magic. The 60hz preset quickly stopped impressing me, so I clicked between 80 and 100. For some reason I really loved the 100hz but it sounded a bit loud. I made a 4rd preset at 91hz since at that point the subs start to dip a little and played Sly Stone If You Want Me To Stay. Larry Grahams bass magic kind of sealed it from there on. It allw orks fantastic and the sub department, im totally done and complete. The main speakers though, they definitly need replaced. The Mb Quart do Loud very well but its not very detailed, but shouty and simply not good enough. For now though, its a 2 week well spent hours of fiddling.

Included the .mdat file from today if youre interested.