Novice needs help!

[Bunandburger]

Hello, I'm new to all of this and I'm hoping that someone out there can help. Seems as though I have my subs aligned well, however after about 50Hz it pretty messy. I tried to apply EQ but it seems to have no affect. Can anyone help?

 

[Todd Anderson]

Do you have any measurements to share? Can you give some details about your subs, system, and room?

 

[Bunandburger]

I have dual GSG Mini Marty subs with 18” Ultimax drivers. Each powered by their own Crown XLS 2002 (2100w bridged). My receiver is an Anthem MRX720. Attached is a photo. The red line is a raw measurement and the green is after a house curve was added. EQ seems to have no affect above 50Hz. I’m sure that it’s user error.

 

[Todd Anderson]

Where do you have the subs positioned?

 

[Bunandburger]

1/4 and 3/4 across the front wall.

 

[Grayson Dere]

After running ARC do your speakers return a good result?

 

[Todd Anderson]

Hopefully, some others will chime in here, but based on your graph, I'd say it's time to try them in some different positions in the room. I'm assuming your x-over is 80Hz? The region between 50 and 80 pretty rough. For some rooms, the 1/4 points work well. But, it's not always the best place.

 

[Bunandburger]

I have not run room correction yet. I was under the impression that I need to get the subs dialed in first.

 

[Todd Anderson]

I'd definitely take your time and move them into different positions around the room prior to room correction. Each move, measure from your primary seating position. Make sure output is leveled at 75 or 80dB and take measurements. May have to tweak phase somewhat.

You should be able to smooth out that mid-bass area decently well. Then apply correction

 

[Wayne A. Pflughaupt]

What equalizer are you using?

Room pictures or a diagram would be helpful.

Regards,
Wayne

 

[Bunandburger]

MiniDSP 2x4HD.

 

[Todd Anderson]

Oh. Okay... I see the problem. Your subs aren't big enough!

 

[Todd Anderson]

Do you have a lot of freedom as to where the subs can go? Or are you restricted to the 1/4 points on the front wall? (Visually, your room looks great, by the way!)

 

[Grayson Dere]

MiniDSP 2x4HD. View attachment 32241

WOWZAAAA!!!! Are those subs off the shelf or custom made? They are quite impressive : )

 

[Bunandburger]

It was a flat pack that I assembled. I also finished them with a veneer and stained them. My wife wouldn’t allow them I. The living rooM if they were just MDF.

 

[JJGR]

There are many factors involved that can cause that frequency response. Here are a few:

The sound coming out of the ports can reflect off the floor and arrive out of phase with the sound coming out of the drivers at many points in the room. If the graph you posted is the subs by themselves, that may be your problem.

If the chart includes all the speakers, then you may have phase issues between your subs and your floor speakers. If so, have you tried reversing the phase of your subs to see if it improves or gets worse. Another way to possibly get an improvement is to EQ so that the crossover between the subs and the floor speakers is sharper. You could also try moving your floor speakers further back or forward to find a sweet spot.

 

[Bunandburger]

The chart is showing only the sub measurements. Maybe I should sweep with the towers.

 

[JJGR]

If you sweep with the towers, depending on their low frequency extension, you may see a better response curve. It would be important, however to check their frequency response alone and with the subs.

Normally, if your towers go down to 50 Hz, you should cut off the subs at 50 Hz.

 

[canizara]

I myself would do this in this order using REW + lot of patience in each step. Longer speaker and power cables will be best:

1. Set subwoofers at one designated spot and set the gains of each at the same level.
2. Experiment put each subwoofer at a location where there is better bass response. Furniture sliders make this easier.
3. Play around with phase. One sub may need a complete different phase than the other.
4. Play subwoofer distance from the receiver. If you receiver does not have sub distance setting for each then I would keep both of them equidistant for main listening position (I guess you can also use the MiniDSP on this later)
5. When there's a semblance of bass smoothness only then you start using the MiniDSP

My 2 cents so good luck