The room is 16'5" x 10'8" x 8'3". The room is has a closed closet on the right side with heavy wood doors and it narrows in the rear of the room. There is also a entrance door on that side. There are big windows along the left side and some more on the front wall. The rear wall is has a upholstered 3 inch foam panel that runs wall-to-wall and floor-to-ceiling. The walls and ceiling are drywall.
The measurements I took before installing the treatment were done with AudioTools iPhone app with a calibrated mic and a hand clap just to get some quick readings. At that time the room had a foam bed rest vertically along the back wall, covering some of the upholstered foam wall. I also had four 36 x 48 x 8 sofa cushions used as makeshift absorbers. Two on the side walls and two between the speakers and fabric sofa. The window had fairy lighweight linen curtains. These are the measurements:
Below are rendering of the acoustic design:
The design has modular custom 22" thick bass absorbers on the front wall covered with Alpha 2A panels. There are two full range Soffit Traps in each of the the front wall corners. There are four Monster Traps on each side with range limiters behind the speakers. And four Alpha 6A panels on the reflections points on the side walls. There are 8 Monster Traps on the ceiling. The ones over the listening position have scatter plates, the ones in the rear of the room are full range.
We suspect that a lot of energy around 250 Hz is being lost out of the double pane windows as there is 10dB dip at that frequency that a eq boost will fix. I'm going to frame out the windows and cover the insulation and 5/8 drywall. Hopefully that fixes the problem.
Yesterday I removed the scatter plates from the rear wall and replaced with 1/8 hard board to increase the reflections on the back wall. The three lower alpha panels in the middle of the rear wall are left full absorption. Doing this increased the decay times however, the frequency curve was to tipped up in the mids and highs so I turned the side Alpha panels 180 degrees to run them broadband which flatten out the curve. The room is starting to sound a lot better. It still has a low RT60 in the mids but at least the emotion and beauty is coming back into recordings. I'm going to continue to play around with moving/removing panels until I get the desired results. And hopefully the covering the windows will help. I plan on building those on Monday. I will report back once I get things more dialed in,
