# Need Room Advice (rew and sketchup pictures included)



## evilskillit (Oct 7, 2008)

This is my small music room dedicated to 2 channel listening. I realize now that I need a bigger room, but that is just not currently possible. So please check out my graphs and dimensions and let me know what I may be able to do.

First, the room. The 4' high things in the corners are subs, the thing between the speakers is the equipment rack. The guy is standing about where I sit and the space behind him is a stupid nook that is currently holding stuff.


















Sub only plot.









Sub w/ mains crossed at 80hz 4th order.









I think the 60hz null is a floor/ceiling bounce. If you play a 60hz tone and walk around its pretty weak everywhere in the room. I don't know if anything can be done about that short of filling the room with giant cardboard tubes. What I think can be dealt with, and what puzzles me is the big fat wide hot spot between 300hz and 1khz. That seems like I should be able to do something to chill it out a bit, so please help me out.

Currently the speakers are placed per the Cardas speaker placement guide. I don't know that moving them will help much. The room also contains an arm chair and some miscellaneous storage stuff. It has carpet, walls and ceiling are sheetrock. I have no room treatments whatsoever. Also my budget is pretty minimal so what are the most effective and least expensive things to do in my situation?


----------



## SierraMikeBravo (Jul 1, 2007)

Hi!

Given your budget specifications, the first thing I would do is move the subs out of the corners. All you are doing with that is exciting all modes at the same time. Also, not sure how you measured things, and that often can be more revelaing than anything else. You really should do a spatial average rather than a single point. Best wishes!


----------



## evilskillit (Oct 7, 2008)

Ok, not sure how to do a spatial average. I'll have to look into it. However other than that fat null at 60hz, which is there no matter where I put things (except one configuration I'll talk about in a second, my bass is smoothest with the subs in the corners like that.

I had the subs all the way infront of me against the front wall and all the way behind me against the back wall and the response was similar but a bit rougher with a big peak kicking in below 30hz. I also tried having the subs right next to me on both sides and while it measured pretty flat up to 60hz with a few little spikes along the way the bass sounded really quiet, even with the volume turned up pretty high. I did a bit of research and found a 6 page article about room placement of subs and it showed that on average you get smoother response with the subs in opposite corners like that. I can always try different things tho.

As for how I measured I basically just put the mic about where my head is when I listen and did a REW sweep. This room is basically just for me to sit in and listen to music, there are no other chairs and I rarely have other people in there with me, so I figured measuring from where I sit would be the best way to go but if you guys need other graphs let me know and I'll see what I can do.


----------



## glaufman (Nov 25, 2007)

In your room, 60Hz corresponds much more closely to a predicted mode across the width of the room than floor-ceiling. One thing to do is look at the waterfall, and take plots of each sub by itself, to make sure it's a mode and not phase cancellation between the subs... 
If you want to to the spatial averaging as Shawn suggested, take multiple scans, moving the mic each time, you can plot them all on the "average" tab in REW, which you can then set to average them for you.
I also like to look at the different mic position scans superimposed on top of each other.


----------



## SierraMikeBravo (Jul 1, 2007)

Hi!

Peaks are much less of a problem to deal with than nulls. You can deal with peaks a little easier IMHO via many methods, but nulls are more of a pain to deal with. I would take Greg's suggestion and do exactly the method he described. You could have placed the mic in a bad spot, too, which is why a spatial average will be generally more revealing of how the listening area is behaving. Best wishes!


----------



## evilskillit (Oct 7, 2008)

Ok, well the wife and kid are going out shopping tonight so I might be able to get the time to actually do this. When I do I'll post the results.

Average1








Average2








A Waterfall


----------

