Engineering services

Acoustic material testing

Microflown Technologies testing division offers possibilities for the in situ measurement of the acoustic reflection coefficient of materials. The possibility of in situ PU surface impedance measurements for instance allows verification of performance of (building) materials as installed, which is simply not possible with (destructive) Kundts tube type of measurements. Furthermore, although widely used and standardized, Kundts tube measurements are not always very reproducible and realistic.

The PU surface impedance method can provide results with a high spatial resolution:

  • under both normal and oblique angels of sound wave incidence
  • homogeneous and locally reacting materials
  • diverse materials as foam, asphalt, metal foam, liners and so on

For each sample, a report is generated:

  • frequency range: 300Hz till 10kHz
  • angle of sound wave incidence

Example pages of a report

Three types of services are provided:

  • weekly rent of PU in situ set up
  • as above, including engineer
  • in house testing services, simply send your samples to us and we will do the work


  • ArcelorMittal
  • Nokia

For more information or questions please contact