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Discussion Starter #1
Room is 19'4 x 13'9 x 7'5, drywall and 2x4 construction.

From the back-left


From the front-right


0-200hz, all channels+sub playing


0-4khz, all channels+sub playing 1/3rd smoothed


As you can see, I am fighting a 25-35hz peak, and a "void" at 125-155hz, otherwise the room would be sitting happily at +/- 3-4db across the whole spectrum. I only have a simple Pioneer vsx-1021 receiver, so I am limited in the EQ possibilities (minimum of 60hz on the standing wave filters). Sadly, the huge peak (room length mode) is terribly audible.

Now, I have yet to do any treatment in the room itself. Is this something that should be electronically EQ'd out, or removed/reduced with treatment? I will be ordering OC703 to wrap the duct along the left-side, which would make it very easy for me to build a 6"x28" soffit to match on the right side as well. That said, I don't have much room to treat the front or back walls (where I assume you would treat to remove a length-dictated room mode). ...not to mention, there is certainly a cost associated, and won't want to be wasting money that could easily be spent on a miniDSP.

Thoughts? Ideas? Questions?

Thanks in advance,
--billyM
 

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If your room decor allows, bass traps will help smooth out your response. Lots of good info here about how to build your own. Also, our friends at GIK make excellent traps - I have several myself. Several styles and colors are available, including art panels:

http://www.gikacoustics.com/products.html

bpape frequents this forum and is an excellent source for advice.

As for electronic EQ, boosting to eliminate dips is a bad idea - it takes a lot of amp power, can overdrive speakers and is effective only for a small listening area due to room modes. EQ cuts don't adversely affect amp power, but again, the benefits are localized. EQ can also result in phase changes around the frequencies where they are applied.

By far, room treatments are the place to start.
 

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Unfortunately, 25-35hz is going to be pretty tough to deal with via treatments. Even our Scopus T40's will only go down to about 30Hz - even with the sealed membrane and an approx 12" thickness. The best way to deal with that peak is honestly to not sit where it exists. Other than that, some selective EQ to cut it is the next best option.

Bryan
 

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Discussion Starter #4
Thanks Bryan for reaffirming my worry (that room treatment would not be suitable for my large 30hz peak) and that gives me direction on how I treat it specifically.

The second question is, what frequency range do I need to be looking at treating the first reflection point? I have those white doors on the left side of the room that need to be covered, so it may as well be in absorptive panels (and mirrored on the right side of the room.

Lastly, if you notice my rear and side surrounds in the second photo, how would you suggest treating them to decrease cross-reflection of the sides and mains-reflections from the rear?

Thanks in advance,
--billyM
 

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Not too worried about the rear channel reflections other than off the front wall. If you have the space you could diffuse it but we don't necessarily want to kill them.

Side wall reflections from the front channels, go as thick as you can. 4" is not too much.

Bryan
 

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Discussion Starter #6 (Edited)
Thanks again Bryan,

I have begun measuring for the first reflection point absorptive panels as well as figuring out how I will wrap the duct-work and screen.

First-things-first, I have the second sub (Klipsch RW-12d) arriving tomorrow.
(the Athena subwoofer is pictured, but was replaced a few weeks ago with the first RW-12d)

I'll post up new graphs once it arrives and then go from there!

--billyM
 
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