Lubreeka Studio - Control Room (Re)Design

Hello everyone! I have been reading and "lurking" in this forum for a long time. Recently I decided to (re)design the control room of my small studio and put on some acoustic treatment, because after working for two years with just small bands and stuff, there have been some interesting opportunities as of lately and I want to make the best I can out of my studio. So, here we go: My relatively small control room has a length of 3.26 m, a width of 3.07 m and a height of 2.91 m. My room ratio sucks, don't bother calculating it! I have decided to treat my room in stages. In the first stage I want to treat the frequency range below 100 Hz. My target frequencies are the first three modes between 50 and 60 Hz (52, 55, 59 Hz). I decided that I would built three diaphragmatic absorbers after the design in Everest's handbook of acoustics. I used wooden panels with surface density m=4 kg/sq.m and according to the formula I needed a 30cm spacing in the corner. The fourth corner cannot be treated because it is very close to the door and there would be no room for the door to open. I also wanted my absorbers to have a large bandwidth. I built those three absorbers during the weekend and the results are quite good, although not exactly as expected. The problem was that two of the corners had irregular shapes that did not allow a depth of 30 cm, which raised the effective frequency of the absorbers. From the measurements it seems that the effective frequency of the absorbers is around 70 Hz with a 20 Hz bandwith. I attach photos of the absorbers and measurements of the room before and after treatment. Next, I plan to treat the frequency range between 100 and 300 Hz, especially a resonance frequency at 120 Hz.

And some more measurements...

That's not an awful lotta wool over there in the corners... Those "traps" look more like a hollow space that way. My advise is to put more volume of wool in the corner. Atleast 4" thick. (looks like u used 2"). The piece of MDF will now resonate prolly more than you would hope for (I can imagen you didn't calculate that exact board piece to act as a resonator trap) Got any design pix? (as in, the whys and hows of your plan)

Hi, to display it... Maybe it could be a way to change the height of the room in any way. Its nice to have a room with 2,91m but shifting the 0 0 x modes into the gap between the others could help you. Theoretically... With a height of 250 ..of 260 And the space above this new ceiling could be used for absorbers best regards

Hey, andy...that's an interesting idea! I was considering constructing a helmholtz resonator centered at the remaining peak around 55 Hz, but lowering the ceiling might help also. Ro, I don't think I need to increase the damping of the resonating panel. The problem is that the irregularities of the corners varied the depth more than it should, so the resulting resonating frequency was higher than I intended. I will check my design again though and post some more info from next week...I'm off to AES conference in Munich tommorow!

Ro, I don't think I need to increase the damping of the resonating panel.

So that's a panel absorber? I would have thought that a deep bass trap would be more use in the corner, and a panel trap along the wall... - Stuart -