Measure Room Acoustics & Reverberation Time (RT60) per ISO 3382 & DIN 18041
Impulse clapper, dodecahedron pink noise or chirp correlation (DIN EN ISO 18233): Which measurement method delivers compliant data without back pain and without contestable 125 Hz errors?
1. Quick On-Site Check (Impulse)
Impulse clapper or FRI source for fast preliminary tests in halls and classrooms without mains power.
2. Chirp Powerhouse (Akulap)
0.3 W to 10 W chirp replaces 1600 W noise. Measure just 5 dB above ambient noise during regular office hours. 1-click report.
3. Classic Dodecahedron
360° omnidirectional radiation for room and building acoustics per ISO 3382 / ISO 140. 100% rent-to-own credit on new Akulap, Ntek & Lookline units.
The "0.3 W vs. 1,600 W" Chirp & Background Noise Simulator
Experience live why traditional interrupted pink noise collapses under ventilation noise in the 125 Hz band (DIN 3382 error index > 400) and how cross-correlation per DIN EN ISO 18233 converts duration into SNR.
💡 Physics Rule: Doubling duration = +6 dB SNR gain (or -6 dB required amplifier power)
The Magic of the Logarithmic Sine Sweep
How to Measure RT60 with Pink Noise & the NTi XL2
Akulap Tutorial: Messung der Nachhallzeit mit Chirps
Die Chirp-Methode: Nachhallzeit messen mit kleinen Lautsprechern
DIN 18041:2016 Target RT60, Schroeder Frequency & "Never Excel Again!"
Calculate the target reverberation time Tsoll for room groups A1 to A5 including the ±20% tolerance band and discover how Akulap averages directly from impulse responses instead of manual spreadsheet work.
Akulap DIN 18041 Plugin calculates equivalent absorption area for unoccupied rooms automatically per DIN 18041:2016.
⚡ "Never Excel Again!" – Why Spreadsheets Are Not Room Acoustics
- • Manually trigger 6 to 12 individual positions on-site
- • Tediously copy CSV files or screenshots onto USB drives
- • Hours of manual typing into fragile custom Excel spreadsheets
- • Arithmetic averaging of raw numbers (normatively flawed as sound decays logarithmically)
- • High error vulnerability and zero physical access to raw impulse data
- ✓ Fully automated multi-point measurement with Akulap Mobile or PC
- ✓ True impulse response energetic averaging algorithm
- ✓ Automatic overlay of DIN 18041 tolerance envelopes & occupant absorption
- ✓ 1-click generation of fully compliant HTML/PDF audit reports (all 14 ISO 3382-2 mandatory items)
- ✓ Universal WAV importer: Seamlessly imports and averages existing recordings from NTi XL2, Bedrock or Svantek!
Nachhallzeit normgerecht mitteln – Nie wieder Excel!
Why RT60 Alone Is Blind – and Why Open-Plan Offices Enforce Chirp
Interrupted noise yields a single number and discards 90% of spatial data. The Akulap chirp impulse response extracts RT60, clarity, room modes and mandatory full-STI in a single pass.
Interrupted Noise (Handheld Meter)
- ✕ Delivers solely RT60 numbers (EDT, T20, T30)
- ✕ Zero insight into discrete reflections, flutter echoes or initial time delay
- ✕ Zero room mode analysis below Schroeder frequency
- ✕ Only direct STIPA feasible (strictly prohibited in open-plan offices per ISO 3382-3)
- ✕ Extreme SPL required – collapses under ambient background noise
Akulap Chirp Impulse Response (Room DNA)
- ✓ Complete reverberation time RT60 in 1/3-octave and octaves (ISO 3382-2)
- ✓ Clarity indices for music & speech: C50, C80, definition D50, centre time TS
- ✓ 3D waterfall spectrum & cumulative decay plot locating standing waves
- ✓ Indirect full-STI per DIN EN 60268-16 & DIN EN ISO 3382-3
- ✓ Silent measurement in occupied office during business hours (0.3–10 W)
🚨 Standard Fact-Check: DIN EN ISO 3382-3:2012-05 for Open-Plan Offices
In open-plan offices, over-damped reverberation is harmful because speech fragments remain intelligible over long distances. ISO 3382-3 strictly mandates measuring distraction distance rD (STI < 0.5), privacy distance rP (STI < 0.2), spatial decay rate D2,S and A-weighted speech SPL at 4 m (Lp,A,S,4m). Mandatory standard requirement: Speech intelligibility must be derived via full, indirect STI from the measured impulse response! Simplified direct STIPA methods (used by handheld meters like the NTi XL2) are strictly NOT permitted per ISO 3382-3. Akulap (Art. 3303020) with a calibrated dodecahedron guarantees full legal and normative compliance.
The DNA of Room Acoustics: Impulse Responses Explained
STI & STIPA: Warum RT60 für Räume & Büros nicht reicht
Select Your Measurement System: Impulse, Chirp or Dodecahedron
Configure your individual measurement system. All prices are calculated live. Add your selection directly to your quote with a single click.
Path A: Impulse Entry
For quick on-site orientation without power outlets (schools, gyms, basic building inspections).
Path B: 2.5 kg Chirp Powerhouse
The modern professional system for acoustic consultants. Measure during business hours with extreme noise suppression.
Hard- & Software Paket inkl. USB-Mic & Aktivlautsprecher
Path C: Classic Dodecahedrons
For building and room acoustics per ISO 3382 / ISO 140. Purchase, demo units at 30% savings & weekly rental with 100% credit.
* All prices net plus statutory VAT and plus shipping costs (FCA Dresden).
Frequently Asked Questions about RT60 & Room Acoustics
Can reverberation time (RT60) per ISO 3382 be measured without a heavy dodecahedron and with HVAC running? ▼
Yes, absolutely. Under DIN EN ISO 18233 (correlation methods), logarithmic sine sweep (chirp) mathematically converts duration into signal-to-noise ratio (SNR). Doubling duration yields +6 dB SNR. While interrupted noise on handheld meters collapses with 50 dB ventilation noise in the 125 Hz band (error index C > 400, requiring 1,600 W power), Akulap chirp achieves standard-compliant results with just 0.3 W to 10 W. Using our compact 2.5 kg active speaker (Art. 6002 for 199,00 € net (236,81 € incl. 19% VAT, plus shipping costs (FCA Dresden)) or weekly rental Art. 20008 for 30,00 € net (35,70 € incl. 19% VAT, plus shipping costs (FCA Dresden))), you can measure reliably just 5 dB above ambient noise – even during regular office hours.
Why is a handheld meter with direct STIPA noise (such as NTi XL2) insufficient for open-plan offices per ISO 3382-3? ▼
DIN EN ISO 3382-3:2012-05 strictly mandates measuring distraction distance rD, privacy distance rP, spatial decay rate D2,S and speech level Lp,A,S,4m using full, indirect STI derived from the room impulse response. Simplified direct STIPA methods (standard on NTi XL2) are explicitly NOT permitted under ISO 3382-3. With Akulap ISO 3382 RT60 Module (Art. 3303018 for 750,00 € net (892,50 € incl. 19% VAT, plus shipping costs (FCA Dresden))) and Open-Plan Office Module (Art. 3303020 for 850,00 € net (1011,50 € incl. 19% VAT, plus shipping costs (FCA Dresden))), you calculate true, audit-proof full-STI.
How do I eliminate manual transcription of RT60 data into Excel when reporting per DIN 18041:2016? ▼
Through Akulap Room Manager: Rather than logging isolated numbers and averaging them linearly in error-prone spreadsheets, Akulap saves the complete impulse responses. The spatial average is recalculated energetically from the underlying decay curves. With the DIN 18041:2016 Plug-in (Art. 3303024 for 399,00 € net (474,81 € incl. 19% VAT, plus shipping costs (FCA Dresden))), target curves and ±20% tolerance envelopes for room groups A1–A5 are overlaid automatically, including occupant absorption correction, and exported as a compliant PDF report. You can also import existing WAV recordings from NTi XL2, Bedrock or Svantek meters directly.
When do I still need a dodecahedron speaker or impulse clapper – and can I rent them? ▼
An impulse clapper (Art. 6051 for 99,00 € net (117,81 € incl. 19% VAT, plus shipping costs (FCA Dresden)) or rental Art. 20010 for 15,00 € net (17,85 € incl. 19% VAT, plus shipping costs (FCA Dresden))) is the fastest battery-free tool for preliminary surveys. A dodecahedron speaker is required whenever tenders or official building acoustic certifications strictly require 360° spherical radiation per ISO 3382 / ISO 140. You can purchase brand-new units like Ntek Omni 4 LT (Art. NtekLS4LT for 2500,00 € net (2975,00 € incl. 19% VAT, plus shipping costs (FCA Dresden))), choose certified demo units (Art. NtekLS4HP_SH for 2150,00 € net (2558,50 € incl. 19% VAT, plus shipping costs (FCA Dresden))) at 30% discount, or rent on a weekly basis (Art. 20006 for 220,00 € net (261,80 € incl. 19% VAT, plus shipping costs (FCA Dresden)) or rental package Art. 20005 for 250,00 € net (297,50 € incl. 19% VAT, plus shipping costs (FCA Dresden))) – with 100% rent-to-own credit towards future purchases.