Measuring Sound Absorption with DaSH

M+P’s DaSH Sound Absorption Measurement system makes it easy to measure and assess the absorptive qualities of road surfaces, whether in the lab (using test cores) or in-situ.

Acoustic absorption is an important property of noise reducing road surfaces, like porous asphalt. But also for test tracks with dense asphalt, where only a certain degree of absorption is allowed (eg. ISO 10844).

DaSH is designed in compliance with ISO  10534-2 “Acoustics -- Determination of sound absorption coefficient and impedance in impedance tubes -- Part 2: Transfer-function method “ and ISO 13472-2 “Acoustics -- Measurement of sound absorption properties of road surfaces in situ -- Part 2: Spot method for reflective surfaces”.

Using our wealth of experience in the field of noise reducing pavements, we’ve designed a measurement system that quickly and reliably assesses the absorptive qualities of noise reducing surfaces, in the lab using test cores, or in-situ.

A unique feature of the system is the use of the three-microphone method. An extended method, developed by M+P, to suppress the influence of interference at the microphone positions.


  • Absorption measurements of test cores in the lab according to ISO 10534-2.
  • Absorption measurements of reflective surfaces in-situ according to ISO 13472-2.
  • Development and optimization of noise reducing pavements.


  • All-in-one: integrated measurement system that quickly delivers final results on-site and in the lab.
  • Accurate: the system uses the three-microphone method, an extended method developed by M+P to suppress the effect of interference at the microphone positions.
  • Practical: the entire system fits in one flight case.
  • Reliable: the system is used extensively in various projects over many years.