Subwoofer Performance Tuning

[bigkrazy155]

I've recently made some purchases and I need some help/advice on how to get the most out of my new toys.

I'm running my new Monolith 13in with a Denon x3800h receiver. I've also added a piddly old Uber10 in the back of the room to hopefully open up opportunities to even out the response. (Uber10 to be upgraded later.)

I took the attached measurement from the MLP using a Umik-1 and REW after gain matching, running audyssey and constructing a custom curve in MultEQ (which helped only a little).

Is it possible to make the response sufficiently flat with the tools I already have or is the dirac live upgrade or a minidsp going to be necessary?

Thanks in advance for the input!

 

[TLS Guy]

View attachment 63325

I've recently made some purchases and I need some help/advice on how to get the most out of my new toys.

I'm running my new Monolith 13in with a Denon x3800h receiver. I've also added a piddly old Uber10 in the back of the room to hopefully open up opportunities to even out the response. (Uber10 to be upgraded later.)

I took the attached measurement from the MLP using a Umik-1 and REW after gain matching, running audyssey and constructing a custom curve in MultEQ (which helped only a little).

Is it possible to make the response sufficiently flat with the tools I already have or is the dirac live upgrade or a minidsp going to be necessary?

Thanks in advance for the input!

What mode are you using the sub in, and what is the size of the room. That response is not bad for the MLP. You are only using one sub, so a fall off at the MLP might be expected, then it looks as if you have a room mode taking over, but that is in the deep bass, and probably not unpleasant. I bet that varies a lot with mic position though. I think using a lesser sub, will always make matters worse, so I would ditch that for sure.

 

[bigkrazy155]

Thanks! I'm running the sub in extended mode with all ports open. I've remeasured with the monolith only, which is the green line. Can I do better?

 

[TLS Guy]

Thanks! I'm running the sub in extended mode with all ports open. I've remeasured with the monolith only, which is the green line. Can I do better?

View attachment 63326

What are your other speakers? How is the crossover set? Also how are they phased? It looks as if there may well be an out of phase issue at crossover..

 

[bigkrazy155]

I measured using ASIO and only ran the sub channel. The phase on the back of the sub is at zero. The mains are JBL Studio 590 (crossed at 80hz), center is Infinity RC263 (80hz), Infinity RS152 side surround (110hz), JBL Studio 530 rear surround (80hz), Dayton Audio ME650C x4 on the ceiling (120hz). I used audyssey identified crossover points but bumped them all up to a minimum of 80hz as I understand this to be best practice generally.

I haven't messed with phase settings on any of the speakers.

 

[TLS Guy]

I measured using ASIO and only ran the sub channel. The phase on the back of the sub is at zero. The mains are JBL Studio 590 (crossed at 80hz), center is Infinity RC263 (80hz), Infinity RS152 side surround (110hz), JBL Studio 530 rear surround (80hz), Dayton Audio ME650C x4 on the ceiling (120hz). I used audyssey identified crossover points but bumped them all up to a minimum of 80hz as I understand this to be best practice generally.

I haven't messed with phase settings on any of the speakers.

That is helpful.

They are all pretty good speakers, with the exception of the side surrounds, which are awful and need to go.

I would try using the right and left speakers full range, and bring the crossover in at 80 Hz. I would cross the center over at 100 to 120 Hz.

The surrounds at 80 Hz.

I would do measurements with the sub phase control at 90 and 180 Hz, and show the responses here. Get rid of the miserable subs and just use the Monolith.

I think you will get a more uniform response with the mains set to large and supplemented. I have a strong hunch you have a phase issue with the sub, which you will need to look into with measurements.

 

[bigkrazy155]

I did realize recently that my side surrounds need to go but I don't have replacements picked out yet. The room is about 21x11, with 11 being the width so whatever it is will have to be low profile or go in the walls. I realized I never got back to you on room size also. The main area is about 1800 ft cubed but also opens up to a fairly tall stairwell that adds close to another 1000 ft cubed.

I was able to take a few more measurements. When measuring my sub only with different phase settings, literally nothing changed. Also I figured out I'm not smart enough to measure FR+FL+SW with Java or ASIO4All. So I've attached a couple of charts that show FL+SW and FR+SW with different phase settings. Looks like running the FR+FL as large is promising!

 

[TLS Guy]

I did realize recently that my side surrounds need to go but I don't have replacements picked out yet. The room is about 21x11, with 11 being the width so whatever it is will have to be low profile or go in the walls. I realized I never got back to you on room size also. The main area is about 1800 ft cubed but also opens up to a fairly tall stairwell that adds close to another 1000 ft cubed.

I was able to take a few more measurements. When measuring my sub only with different phase settings, literally nothing changed. Also I figured out I'm not smart enough to measure FR+FL+SW with Java or ASIO4All. So I've attached a couple of charts that show FL+SW and FR+SW with different phase settings. Looks like running the FR+FL as large is promising!

View attachment 63341View attachment 63342

That is really good now. LFE+main is often the way to go, but the mains need to be capable like yours. I have done a lot of investigation on this, and LFE + Main usually gives the best in room response and sounds the best. We do not recommend it often enough.

There is improvement as I suspected with the sub phase at 180 degrees. You have that null at 140 Hz, but it is narrow, and what we call low Q. That is very unlikely to be audible at that range.

If you like the sound of it, I would leave everything alone, and just enjoy it. If you have enough bass, I doubt you need another sub. Your results are well towards the top of the pack now.

 

[ski2xblack]

Very respectable, and interesting, results.

Interesting due to the setup you describe, specifically that you're running the mains full range. That first graph looks like what you would get with the main crossed to the sub almost perfectly at 90 Hz.. One would typically only get those sort of measurements if the slopes, levels, and crossover freq is damn near perfect, and the sub co-located with the speaker. Compare the 0 deg plot with the 180 degree one. That narrow dip in the 180 deg graph is a telltale sign that the crossover is nailed, and that 0 deg is the best setting.

But since that's not the case, it's just a wierd coincidence. Results look good, though.

 

[TLS Guy]

Very respectable, and interesting, results.

Interesting due to the setup you describe, specifically that you're running the mains full range. That first graph looks like what you would get with the main crossed to the sub almost perfectly at 90 Hz.. One would typically only get those sort of measurements if the slopes, levels, and crossover freq is damn near perfect, and the sub co-located with the speaker. Compare the 0 deg plot with the 180 degree one. That narrow dip in the 180 deg graph is a telltale sign that the crossover is nailed, and that 0 deg is the best setting.

But since that's not the case, it's just a wierd coincidence. Results look good, though.

As I said we don't advise LFE + main often enough. If the mains are capable that more often than not gives the best result. The 180 phase is giving the best response, as there is only one null and not 3.

 

[bigkrazy155]

Fantastic, I very much appreciate the feedback. I'm still a bit confused on the phase decision. It sounds like you guys are saying the opposite. Also should I set the mains to xo at 40hz and test from there? That should at least allow me to measure both fronts plus the sub at one time.

Edit: 40hz was a bad idea

 

[TLS Guy]

Fantastic, I very much appreciate the feedback. I'm still a bit confused on the phase decision. It sounds like you guys are saying the opposite. Also should I set the mains to xo at 40hz and test from there? That should at least allow me to measure both fronts plus the sub at one time.

Edit: 40hz was a bad idea

Use 180, you only have one null then and not three. Do not go down to 40 Hz. The optimal place to crossover is the F3 of the speakers + 50% or thereabouts. I worked that out for you already.

 

[ski2xblack]

Sorry for the confusion. We're not really saying anything different, as my post was a bit of a nonsequitir about something that is quite different than your rig.

Agree w/ TLS on running capable mains full range. Better modal smoothing, and avoids another TLS truism about not separating the fundamentals from the harmonics, for a more natural, convincing result.

You could try a few sweeps with the 40Hz high pass, nothing wrong with that as your mains head south just below. After all, you listen to music with L, R and sub together, might as well measure that too. But your L+sub and R+sub plots look pretty good.

 

[TLS Guy]

Sorry for the confusion. We're not really saying anything different, as my post was a bit of a nonsequitir about something that is quite different than your rig.

Agree w/ TLS on running capable mains full range. Better modal smoothing, and avoids another TLS truism about not separating the fundamentals from the harmonics, for a more natural, convincing result.

You could try a few sweeps with the 40Hz high pass, nothing wrong with that as your mains head south just below. After all, you listen to music with L, R and sub together, might as well measure that too. But your L+sub and R+sub plots look pretty good.

He has a result now, well at the top end of the pack. Time to let what is good be good. The enemy of good is better. Anymore messing about and we might induce a case of Audiophilia Nervosa!

 

[ski2xblack]

Agreed, it's time for the OP to rock out and not obsess. Try out Huckleberry Blues by Otis Taylor.

 

[Tulonarinchu]

Your setup sounds awesome, and it's great that you're working on optimizing the sound. It looks like you've done a lot already. While Dirac Live or a MiniDSP could help further refine your room's acoustics, you might want to experiment with positioning, acoustic treatments, and different EQ settings within your current setup to see if you can improve the response without additional purchases. Every room is unique, so some trial and error might be necessary. Enjoy the audio journey!

 

[bigkrazy155]

For anyone playing along, here are the final measurements with phase at 180:

I also bumped the LPF up to 250 where it was previously at 150. Thanks for the help gents! Things are sounding awesome!