BAUX Acoustic Tool
Reverberation calculator · in minutes
Calculate acoustic reverberation. Design rooms that sound right, before they’re built.
Set up a project, add as many rooms as you need, and pick BAUX panels for each. The tool calculates reverberation time at 1/3-octave resolution from real ISO 354 measurement data and tells you whether each room is compliant — with a PDF report and before / after audio per room.
Free to use · Save your projects · Internal tool by BAUX
Reverberation result
Current RT (mid)
1.42s
With BAUX (mid)
1.42s
11
National standards
SS · DIN A/B · LEED · WELL · BB93 · NF · CTE · UNI · DL
27
BAUX product variants
Wood Wool · Pulp · X-FELT
ISO 354
Verified αp values
Akustikverkstan · MFPA Leipzig
1/3
Octave resolution
100 - 5000 Hz, 18 bands
Why BAUX built this
Acoustic spec sheets are slow. We made them fast - without losing rigour.
01 · Real measurement data
ISO 354 αp values, not guesses
Every BAUX product variant carries its 1/3-octave absorption curve from Akustikverkstan in Sweden or MFPA Leipzig in Germany - the same labs that supply EU acoustic certification. Each row in the tool cites its report ID.
02 · Multi-standard ready
SS · DIN · LEED · NS · International
Pick your country and the matching national standard auto-loads, target RT and tolerance corridor with it.
03 · Hear the difference
Auralisation before and after
Synthetic impulse-response convolution lets you A/B the room with and without BAUX panels. Download as MP3.
Standards · 11 in the box
Country in, the right standard out.
Each standard is encoded from the original source document - broadband limits, volume-dependent formulas (DIN cube-root, UNI / DL Portugal), octave-band corridors (DIN, UNI), and multi-level targets (BB93, NF Courant / Performant / Très Performant) all live as data. Pick the country and the right room-type bindings, target curve and tolerance corridor load together.
Sweden
SS 25268
Building acoustics standard for offices, schools, healthcare and hotels. Class A / B / C / D targets per room type.
Germany
DIN 18041 (Group A & B)
Group A: speech-critical rooms with T_soll = f(V). Group B: extended-occupancy spaces with A/V minimums.
United Kingdom
BB93 (2015)
Building Bulletin 93 - the Department for Education reference for any UK school project. 17 room types × new-build / refurbishment.
France
NF S31-080
AFNOR office-acoustics standard. Courant / Performant / Très Performant targets across 7 space types.
Spain
CTE DB-HR
Building-code chapter on noise protection. RT limits for classrooms / conference rooms (V ≤ 350 m³) and restaurants.
Italy
UNI 11532-2:2020
Modern school-acoustics standard. T_opt = a·log10(V) + b - volume-dependent and harmonised with DIN 18041 Group A.
Portugal
DL 96/2008
Building-acoustics regulation. Cube-root RT formulas covering offices, restaurants and PA-equipped spaces.
United States
LEED v4.1 ID+C · WELL v2 S04
LEED v4.1 Table 2 commercial-interior acoustic credit. WELL v2 Sound concept S04 available as the voluntary IWBI alternative.
International
Generic
Median targets for projects without a national reference - useful when the country isn't bundled yet, or when the brief is purely commercial.
Auralisation
A specification you can listen to.
Numbers convince acousticians. Sound convinces everyone else. The tool builds an impulse response from the calculated RT60 curve and convolves it with a clean speech sample - so the architect, the client and the facilities team can hear the room before BAUX, and the same room with BAUX, side by side.
- Per-octave impulse response. Built from the same αp data the RT60 chart uses - not a generic reverb preset.
- Before / after in one click. The Before track uses the untreated room; the After track uses your current panel selection.
- MP3 export in the project zip. Two stereo tracks alongside the PDF report - loop them in a presentation, share them with stakeholders.
Impulse response preview
How it works
Five steps. Five minutes.
- 1
Create a project
Name the project, pick country and standard, choose units. Every room in the project inherits these.
- 2
Add a room
Pick a scenario chip — dimensions seed automatically. Add as many rooms per project as you need.
- 3
Surfaces & people
Materials for floor, walls and ceiling, plus occupants and furniture — all discrete absorbers.
- 4
Add BAUX Acoustic Products
Ceiling, walls, dividers. Class, αw and NRC update live as you pick.
- 5
Result & export
RT60 chart, compliance verdict, PDF + before / after audio. Per room — or the whole project in one zip.
Frequently asked
What people ask before they trust the numbers
Where do the absorption values come from?
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Every BAUX product carries its αs curve from the underlying ISO 354 measurement protocol - Akustikverkstan in Sweden for Wood Wool, Pulp and X-FELT Floating, MFPA Leipzig in Germany for the X-FELT panel series. Each row in the tool cites its report ID, so a consulting acoustician can trace any number back to its measurement file.
Is the calculation good enough for compliance documentation?
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The Sabine model with verified αp values is design guidance - typically within ±10-15 % of a measured T60 for rectangular rooms with reasonable absorption distribution. Formal compliance documentation should always be verified with on-site measurement per ISO 3382 by a qualified acoustic consultant. The footer on every PDF report says exactly that. The tool is meant to help you arrive at the measurement with confidence that the spec will pass, not to replace the measurement itself.
Which standards are supported?
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Thirteen standards across ten countries plus an international fallback: Sweden (SS 25268:2023), Finland (SFS 5907:2022), Germany (DIN 18041 Groups A and B), United Kingdom (BB93), France (NF S31-080), Spain (CTE DB-HR), Italy (UNI 11532-2:2020), Portugal (DL 96/2008), United States (LEED v4.1 ID+C and WELL v2 S04), Australia / New Zealand (AS/NZS 2107:2016) and International (WELL v2 S04 plus Generic median targets for projects without a national reference).
What's the difference between Materials-based and Measurement input?
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Materials-based asks for floor / walls / ceiling surfaces and computes the current RT60 using the Sabine model - fastest, good for early-stage design when no measurement exists. Measurement-based asks for a measured T60 per octave band (ISO 3382-2) from a survey of the existing room, uses your curve as the BEFORE state and layers BAUX absorption on top to predict the AFTER state. Most accurate option whenever a real measurement is available. You can switch between the two modes without losing the input from either - useful for sanity-checking the materials estimate against a measurement of the same room.
Can I use my own ISO 3382-2 measurement?
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Yes - on Step 2 pick 'I have an acoustic measurement', then enter T60 per octave band (125 / 250 / 500 / 1 k / 2 k / 4 k Hz) on Step 3. Tell the tool whether the measurement was taken in an Empty, Furnished or Occupied room - it determines whether people / furniture from Step 3 are added on top of the baseline or treated as already captured in the measurement.
What does the 'near target' verdict mean?
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The three-tone verdict is based on the ratio of computed RT60 to the standard's target at the mid-band: green (within 5 % of target - on spec), olive (5-20 % above target - usable but worth tightening if BAUX area allows), red (more than 20 % above target - meaningful gap, the room won't pass without more absorption). The reverberation chart shows the same target as a horizontal line per band so you can see where the shortfall is spectrally.
How are people and furniture absorption values determined?
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Every entry in the People & Furniture step (people seated, office chair, sofa, carpet, curtain, etc.) carries octave-band absorption values from published ISO 354 measurements - the same source the surface materials use. Person values depend on posture and clothing; the tool's defaults assume typical occupied clothing. Winter clothing adds roughly 30 % more absorption per person, summer slightly less.
How are the Before / After audio simulations generated?
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The tool synthesises an impulse response that matches your computed RT60 per octave band, then convolves a clean speech sample through it - once for the untreated room (Before) and once with BAUX panels added (After). The IR is a band-filtered exponential decay model; it doesn't reproduce specific early reflections but does match the perceived reverberation time. Both renders ship as MP3 files in the export zip alongside the PDF.
Does the tool work for open-plan offices?
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It gives an indicative RT60 - useful for sizing BAUX panels. Formal open-plan compliance also requires spatial-decay metrics (D₂,S, L_p,A,S,4m per ISO 3382-3) which depend on screen heights, workstation layout and source-receiver distance. The tool flags this in the verdict text and routes you toward a consulting acoustician for the final number.
What about dividers / free-hanging panels?
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X-FELT Floating Panels are count-based: enter the number of panels, the engine adds 5.6 m² of double-sided absorbing area per panel using the M12 ISO 354 measurement. Requires room height > 2.85 m (panels are 2.8 m tall + clearance for the suspension hardware).
Can I save and come back to a project?
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Yes — create a free account and your projects persist. Each project carries a country / standard / units selection and holds as many rooms as you need, each with its own dimensions, materials, occupancy, BAUX picks and result. Open the project list any time to pick up where you left off, or download every room in a project as one zip from the project view.
Metric or imperial units?
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Both. You pick m / m² or ft / sqft on the project-setup screen and can flip it later from the project header. The internal calculation always runs in metric (SI units); conversion happens at the input and display layers only, so switching mid-session doesn't change the numbers, only how they're shown.