Hello, I am currently trying to adjust the acoustics in my home-studio (mainly for mixing) and need your help to sort out some issues! It's a 2,30m x 3,70m room (yes, it's metric, please continue reading) with carpet on the floor (about 2-3cm). Cieling is about 2,40m high. It also has a small space after the door: My monitors are Mackie MR-5 which are quite fair budget-level monitors placed at ear level, driven by a Motu AudioExpress interface. I measured the response of one of the monitors and it seems quite flat. I am using a Behringer ECM-8000 for measurements. Facts about the room: - when clapping your hands, you can hear a clear metallic ringing lasting about 200ms after the clap. - opening the room door and breaking the small space helps for this, but not completely. - when bass is playing loud in the room, I cannot hear specific bass resonnance in the small space before the door. I have tried placing my traps and absorbers in the following manner: wall traps: 1150 x 575 mm, 50 mm thick, 65kg/m3 corner trap: 575 x 575 mm, 100 mm thick, 65kg/m3 foam absorbers: 1000 x 1000 mm, 70 mm thick, quite light (about 20kg/m3) - wall bass traps are placed about 8cm away from the wall - foam absorbers are put against the wall - closet is open on the right side, filled with clothes The main problems in the room (according to REW measurements) are two persisting bass frequencies: 130Hz and 150Hz that tend to become too present. Questions: 1. During adjustment, the "wall" bass traps and foam absorbers are not held firmly at 8cm from the wall, they are simply placed on a supporting object: Does this heavily effect the performance of the traps? 2. Changing the traps and absorbers placement had little effect on the room's bass response, for example covering the window with a bass trap or not has very little effect. What other factors am I overlooking? I separated the speakers from the desk they are put on by a block of 15cm of foam and made sure the desk was not resonnating/vibrating heavily with bass frequencies. 3. As mentioned earlier, when clapping your hands, you can hear a clear metallic ringing lasting about 200ms after the clap. What can cause this? 4. Can you suggest a potentially more effective speaker placement?