Building Acoustics Measurement Solution

NTi Building Acoustics
Measurement Solutions

The portable NTi XL2 Building Acoustics Kit is ideally suited for use on site. Indeed, With only 7.5 kg and a typical sound power of 120.5 dB, the DS3 Dodecahedron Speaker is built for use on construction sites. In other words, the DS3 delivers an omnidirectional sound with a flat acoustic frequency response. The XL2 Sound Level Meter measures the noise spectrum in the sending and receiving room as well as the reverberation time.

Moreover, using the Sound Insulation Reporter PC Software, you can generate the standard-compliant measurement report on site using.

Kit Components

XL2 Sound Level Meter

Spectrum Analyzer

The XL2 Sound Level Meter measures the noise spectrum in the sending and receiving room. The level difference forms the base of the sound insulation calculation. Additionally a background noise spectrum recorded in the receiving room (without the test signal) allows for a noise correction.

RT60 Reverberation Time

The level difference between two rooms needs to be corrected for any influence of the reverberation time in the receiving room. Therefore, the reverberation time is measured by the XL2 in 1/1 octave resolution (or in 1/3 octave resolution with the optional XL2 Extended Acoustics Pack installed). Further more, the RT60 measurement offers automated triggering for repeated tests using an impulse or gated pink noise as signal source.

DS3 Dodecahedron

The omnidirectional DS3 Dodecahedron Speaker is a lightweight yet powerful sound source for measurement applications in room and building acoustics. Indeed, the DS3 is combined with the remote-controlled PA3 Power Amplifier to make up the Dodecahedron Speaker Set for professionals. Most importantly, the optimized frequency response ensures precise measurements in accordance with the ISO 16283 and ISO 3382 standards.

PA3 Power Amplifier

The portable PA3 Power Amplifier contains a DSP-based signal generator with equalizer. To sum up, in conjunction with the DS3 Dodecahedron Speaker, a pink noise is produced with an acoustically flat frequency response. The equalization ensures that the ISO 16283-1 requirement of ≤ 8 dB difference between contiguous 1/3rd octave bands in the emitted sound is met. In addition, a test signal optimized for maximum sound power is available as well as an external audio input socket.

TM3 Tapping Machine

The remote-controlled TM3 Tapping Machine is a precision impact noise source for building acoustic measurements. Therefore, it is typically used for the assessment of general impacts in dwellings that occur on floors or stairs in a building and can be operated autonomously, due to the built-in battery.

The Tapping Machine complies to the standards ISO 16283-2, ISO 717-2, ISO 10140-3/-4/-5, ISO 140-6/-7/-8, DIN 52210-6, ASTM E492 and ASTM E1007.


  • Calibrated acoustic system for traceable measurements
  • Lightweight omnidirectional sound source with amplifier
  • Simultaneous measurements in sending and receiving rooms using Wi-Fi communication
  • Supports ISO 16283, ISO 140, ISO 717, ISO 10140, DIN 4109, BB93, Document E, ASTM E336, ASTM E413, ASTM E1007, ASTM E989, ASTM E966, ASTM E1332, GB/T 19889, and SIA 181 standards
  • Compact and lightweight 
  • Maximum sound power level 120.5 dB 
  • Wireless remote control
  • Airborne, impact and facade sound insulation
  • Parallel measurements in sending and receiving room
  • Standardized Reporting

Looking for further details information? Check NTi’s dedicated web page:

NTi Building Kit Components

  • PA3 Power Amplifier
  • with built-in noise generator
  • DS3 Dodecahedron Speaker
  • Speaker Stand for DS3
  • XL2 Acoustic Analyzer
  • Extended Acoustic Pack for XL2
  • Sound Insulation Option for XL2
  • M2230 Measurement Microphone
  • ASD Cable for XL2
  • Mains Power Adapter
  • Exel System Case

Optional as required:

  • Remote Measurement Option for XL2 for remote data acquisition with Sound Insulation Reporter
  • Type Approval Option for XL2 for legally-approved measurements
  • TM3 Tapping Machine impact sound insulation measurement source
  • Minirator MR-PRO for white noise or special band-limited test signals
  • Class 1 Sound Calibrator for user calibrations

Contact us !

Would you like to contact us? Or maybe you just want to know more about us? Visit or contact us by email at or by phone at +32 (0) 2 672 95 90.

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