Noise and hearing lab
Our noise lab in Trondheim is equipped to reproduce various noises at typical levels. We have calibrated recordings of several noise situations from process industry that can be played back in the room. Even something as loud as a helicopter landing (110–115 dB, A-weighted) can be reproduced at realistic levels. This enables us to test hearing protection devices and communication equipment in a realistic environment.
When the noise lab is not used for playing back loud noises, the background noise in the labs is low enough to comply with standards of different types of audiometry, included free-field audiometry. This enables us to do standardised REAT testing of hearing protection equipment. Equipment for this kind of testing is also installed in the room.
Equipment:
- 16 JBL 15-inch subwoofers mounted in wall
- 8 Yamaha P700S stereo amplifiers
- 4 Kling&Freitag CA106 loudspeakers
- 2 Tannoy V300 loudspeakers
- 3 Crown XLS802 stereo amplifiers
- 1 dBX DriveRack 260 management system
- Calibrated measuring microphone for level measurements
- Computer for playback and measurements
- If needed: B&K HATS (pictured above)
Building acoustics lab
The building acoustics lab in Oslo can be used both for R&D projects and for full scale measurements of acoustic properties of building components. The equipment can also be used for field measurements.
The lab is accredited by the Norwegian Accreditation for measurements of sound insulation according to NS-EN ISO 10140 part 1 to 5 and sound absorption according to NS-EN ISO 354. The reverberation chamber also complies with NS-EN ISO 3741 for measurement of sound power levels from various types of noise sources.
In this lab we can test the acoustics of large building components such as walls, ceilings, floors and floor covers, and smaller components such as doors, windows, and slit valves. In the reverberation chamber we can measure sound power levels from different noise sources such as fans, HVAC-components and determine the effect of acoustic insulation of pipe lines. You can find more details about this lab on its own page.
Equipment:
- Structurally separated sending and receiving rooms
- Full scale test openings
- Reverberation chamber
- Omnidirectional loudspeakers
- Standardized tapping machine
- Microphones and preamplifiers
- Class I sound level meters
Underwater acoustics lab
We have a large water tank in Trondheim for ultrasonic experiments, smaller-scale underwater experiments, and for testing and calibrating transducers to be used in larger-scale tests in the fjord or the ocean.
We also use the Trondheim fjord as a laboratory for underwater acoustics. An example is the 2 km acoustic communication link between Trondhjem Biological Station (NTNU) and the swimming facility Sjøbadet at Brattøra harbour. We also regularly use NTNU's research vessel Gunnerus. Additionally, we have a large remote-controllable buoy with an underwater acoustic modem, VHF radio, and Iridium satellite communication. It includes an on-board data logger, hydrophone, rechargeable battery pack, solar cells, AIS transponder, active radar reflector, navigation light, and a hydrogen sensor for battery safety.
Equipment:
- Large water tank, with dimensions 4.30 x 1.50 x 2.00 m3
- Smaller tank facilities (aquarium), with dimensions 0.80 x 0.50 x 0.40 m3
- Transducers
- Hydrophones
- Power amplifiers
- Preamplifiers
- Generators/transmitters
- Advanced oscilloscope
- Filters
- Multichannel receiver up to 200 kHz sampling
- Large remote-controllable buoy
- Self-contained underwater acoustic modem matched to the buoy
3D sound and auralisation labs
A calibrated 5.1 surround system can be used to auralise everyday sounds at the correct levels. Calibrated recordings for this are available. Additionally, we have technology for reproducing 3D sound in a virtual auditory display (i.e. head-tracked headphones), though this is not physically restricted to the lab area.
Equipment:
- 5 Genelec G One
- 1 Genelec F One
- Computer for playback
- Axivity WAX9 and Hillcrest Labs FSM-9 IMUs for head-tracking
- A large variety of headphones
Additional labs at NTNU
SINTEF has a close collaboration with the acoustics group at NTNU through the Gemini centre Acoustics Research Centre. We have access to and experience with their labs, which include:
- Anechoic chambers
- Reverberation rooms
- An 2D Ambisonics reproduction system