Time to tap into the great amount of knowledge at AVS. 5 years ago we finished off our basement and put in a dedicated HT room.
My primary goal at the time was sound isolation so that I could watch my favorite action/adventure movies at an engaging volume and not disturb the rest of the family who might be reading, watching TV or sleeping . So far that has worked out. Now I want to tackle a little DYI project to work on improving the acoustics.
Details of the room:
The room has lots of hard, reflective surfaces. To keep the sound in, the walls were made of 1/2" sheet rock + Green Glue + 5/8" sheetrock on staggered 2x6's filled with fiberglass batts. 2 of the walls have poured concrete behind them, and beneath the carpet and pad is a concrete floor. The room's basic dimensions are 14.5' wide x 18' long x 8' high. I have a 2' wide soffit around the perimeter to run wiring, HVAC and rope lighting, so the ceiling is lowered to 7.5' around the edges. The ceiling is also drywalled. Wall surfaces are painted dark colors for a black-out effect and total immersion in whatever is playing on the big screen.
The room doesn't have a lot of depth, so we sit fairly close to the rear wall ( 5' - 6'). The screen wall (I have a FP setup) is dominated by a non AT screen, 115" diag 2.35:1 aspect screen, so there's only about 2' below and 18" above the screen that can be used for absorption. The screen wall is a false wall, so there's 2' of depth behind it that can be used for multiple purposes, one of being a good place to do bass trapping (stacked bundles of fiberglass R19 insulation).
That's the basics of it. I use the room for both movies and music - I'd say I'm 50-50 on that one. I still like 2 channel audio and have been getting back to my analog roots with a growing collection of used vinyl LPs. For speakers I now have a 7.1 set up, with a well-loved venerable old pair of Vandersteen 2 Ce for the main channels. I set the receiver to THX Ultra Cinema mode to convert all 5.1 sources to 7.1 and like the enhancement so far.
I sketched up the room in Visio, so I hope I have no trouble in attaching the file. I tried to be as exact as I could on the dimensions and proportions, as this was the first time I've ever done something like that. I usually like to draw things out the old school way on paper with my t-square and architects ruler.
So my goal is to try to address some problems this room has. I know it is not a perfect room. Dimensions/proportions could be lots better, but there were a lot of obstacles like numerous support posts and massive microlam beams to support an open floor plan on the first floor plus a second story bedroom level. Don't get me started about the support posts ! Some of the subcontracts said they hadn't seen so many posts in a house our size !
Perhaps treating the 1st reflection points will do wonders and treatments for the rear wall. I'd like to hear what recommendations are made for the rear wall - there seems to be differences in opinion on whether or not diffusion would be effective when the seating location is less than 6' away.
BTW - I'm interested in making my own treatments. This is a hobby for me, so I get more out of when I put in my own sweat equity !
Thanks for looking - Bill
Benz's Man-Cave Drawing.pdf 98k .pdf file