**What I'm after:** Concrete-shell room currently treated as a broadband absorber. Fabric + wood slats are going up across the room next — that will scatter/reflect the highs and bring mid/HF decay back up, so I'm *not* asking about over-damping; the slat finish handles the top end. Since slats-over-porous stay transparent to bass, the low-frequency behaviour won't change materially when they go in — so I want to settle bass treatment now, before installing them. The question is purely: does this data say the bass is adequately controlled, or is more bass trapping warranted (vertical-corner broadband, or tuned membrane / MLV)? This is means to be a live recording / mixing / mastering room.
**Room & treatment**
- ~16' × 13.5' × 11' (L × W × H). Bare shell is concrete floor, walls, and ceiling — zero inherent absorption, fully rigid boundaries.
- Walls: two at 3.5" rockwool; the opposing two (one 16', one 13.5') at 7" rockwool.
- Ceiling: ~12" rockwool.
- Soffit bass traps at the wall/ceiling edges, ~15" wide × 12" deep.
- No dedicated vertical-corner traps yet.
- Still to come (not yet installed): fabric + wood slats across the room, to raise HF liveliness.
**Please calibrate to these caveats first**
- Woofer-only measurement: Purifi PTT8.0, no crossover, no DSP alignment yet. The low end will later be brought flat to ~30 Hz, so the sub-80 Hz rolloff/tilt is not a finished result — please discount it.
- The left speaker isn't built yet. Both attached sweeps are the same physical right cabinet measured in two positions, so treat this as two in-room samples of the room, not a matched stereo pair — not asking about L/R matching.
**Setup**
- REW, 2-sweep average, 30 Hz–5 kHz, mic at the listening position. .mdat files attached.
**What the data shows (bass-relevant)**
- Decay is short and clean: broadband 30–300 Hz ~112 ms (Schroeder), and the spectrogram shows nothing ringing past ~50 ms — no sustained modal tails in the measurable range.
- The only sustained LF energy is ~100–250 Hz, and it decays fast.
- A couple of cancellation dips (~126 Hz, ~196/216 Hz) that read as SBIR
**Questions (bass only)**
1. From this data, is the bass already adequately controlled, or is more bass treatment warranted?
2. Beyond the soffit traps already in place, is there justification for adding vertical-corner broadband traps, or is the decay already short enough that they'd add little in the measurable range?
3. Membrane / MLV tuned traps — anything here that would call for them
4. Did I run measurements correctly? Should I DSP and then retake measurements?
Happy to post waterfall, phase, GD, RT by band, or anything else. Thanks.
**Room & treatment**
- ~16' × 13.5' × 11' (L × W × H). Bare shell is concrete floor, walls, and ceiling — zero inherent absorption, fully rigid boundaries.
- Walls: two at 3.5" rockwool; the opposing two (one 16', one 13.5') at 7" rockwool.
- Ceiling: ~12" rockwool.
- Soffit bass traps at the wall/ceiling edges, ~15" wide × 12" deep.
- No dedicated vertical-corner traps yet.
- Still to come (not yet installed): fabric + wood slats across the room, to raise HF liveliness.
**Please calibrate to these caveats first**
- Woofer-only measurement: Purifi PTT8.0, no crossover, no DSP alignment yet. The low end will later be brought flat to ~30 Hz, so the sub-80 Hz rolloff/tilt is not a finished result — please discount it.
- The left speaker isn't built yet. Both attached sweeps are the same physical right cabinet measured in two positions, so treat this as two in-room samples of the room, not a matched stereo pair — not asking about L/R matching.
**Setup**
- REW, 2-sweep average, 30 Hz–5 kHz, mic at the listening position. .mdat files attached.
**What the data shows (bass-relevant)**
- Decay is short and clean: broadband 30–300 Hz ~112 ms (Schroeder), and the spectrogram shows nothing ringing past ~50 ms — no sustained modal tails in the measurable range.
- The only sustained LF energy is ~100–250 Hz, and it decays fast.
- A couple of cancellation dips (~126 Hz, ~196/216 Hz) that read as SBIR
**Questions (bass only)**
1. From this data, is the bass already adequately controlled, or is more bass treatment warranted?
2. Beyond the soffit traps already in place, is there justification for adding vertical-corner broadband traps, or is the decay already short enough that they'd add little in the measurable range?
3. Membrane / MLV tuned traps — anything here that would call for them
4. Did I run measurements correctly? Should I DSP and then retake measurements?
Happy to post waterfall, phase, GD, RT by band, or anything else. Thanks.
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