EXTREMELY Reflective Room is Driving Me Nuts!

[The Numenorian]

I have been using a very reflective downstairs room for a while now, and before, it was sort of an advantage with my small HTIB system. But since I've stepped up into the separates market and have a LOT more power and sound from an rx-v2500 and some large mains, it is really hampering the natural sound I'm looking for! I have these parameters to deal with:

-The room is layed with a hard, concrete-like tile
-Room size is roughly 2200ft^3
-Ceilings are beveled around the edges, like this...

/----------\

...all the way around; my listening position is right under the rear bevel, ten feet from the mains, and the speakers are 3 feet out from the wall below the opposite bevel.

-Walls are sheetrock, covered with basic paint primer and a few layers of paint (can't remember what kind)
-Walls are insulated
-Two bay windows, about 3.5"x5.5"-

one a few feet left and on the wall behind my left main
one more on the adjacent wall, to the left of the left main about 8 or 9 feet

I have used the optimization feature on the 2500, but regardless of its attempts to cancel room modes, the surfaces are still VERY reflective. I've considered relocating to a carpeted room, but I'd rather stay down in the current space which wouldn't get much use if I moved the system. Any thoughts?

 

[fergusonv]

Start building bass traps and get some futniture to diffuse the highs.

 

[Ethan Winer]

> The room is layed with a hard, concrete-like tile ... I have used the optimization feature on the 2500, but regardless of its attempts to cancel room modes, the surfaces are still VERY reflective. <

No electronic unit can cancel room modes satisfactorily, let alone reduce reflections at mid and high frequencies. As fergusonv said you need bass traps, but I'm sure you need absorbers much more than diffusion. Unfortunately, in a room with that many highly reflective surfaces you need a fair amount of acoustic treatment. But once that is done you'll be amazed at the improvement.

--Ethan

 

[sploo]

Hi Numenorian,

Ethan's right (I know because I have the graphs to prove it ).

I too have a room with highly reflective surfaces (painted brick walls, wood floor, solid ceiling) and it sounded foul.

Bass traps certainly helped the low-end, but the biggest difference (for me) was the installation of some aborsption at the first reflection points.

I made my own (mainly due to cost and location issues), see:

http://spikyfish.com/acoustics/
http://spikyfish.com/acoustics/panels.html

However, having seen before/after graphs of a room treated with Ethan's gear, I have no doubt his 'proper stuff' is superior.

 

[twisted3]

placing a thick rug in front of your system will help a lot too.

 

[Joel DuBay]

I feel your pain!


And, you can make your own HF panels or broadband solution panels from rigid fiberglass insulation. A nice stock of Owens Corning 703 or CertainTeed CB300 (identical) will help absorb those high flutter echos you hear in your "ringing" room and help curb your bouncing bass modes to below 80hz!


Begin by bass trapping your vertical corners with 4" of OC703, floor to ceiling. This will assist in trapping bass modes that would otherwise be bouncing around your room and smearing your sound! Next, treat those points that are directly parallel with your listening position and over head. You can do this with a 2" slab of OC703, but why not use 4" instead? You may get a "more Sabins per dollar" outcome with this mode of absorption. Wrap your panels in a breathable fabric, mount them according to your own aesthetics and get ready to hear your system like you have never heard it before! You will be absolutely amazed at the outcome and if you do it yourself, you can save THOUSANDS over some premade commercially available acoustic treatments.

Get us a sketch of your room and we'll get help get you on your way!!

Good luck!