Solutions for Automotive measurements and challenges from M/s. G.R.A.S. Sound & Vibration AS, Denmark.

NVH Challenges: Valid data and efficient test methods have always been important in acoustic noise, vibration and harshness (NVH) testing. As the world leader in developing cutting-edge acoustic sensors, GRAS provides new and improved microphones for more efficient and reliable acoustic NVH testing. This includes a rugged and very versatile standard microphone for a wide variety of acoustic NVH applications as well as highly specialized microphones for very specific applications.

Challenge for Engine noise testing: Measurement method with a high number of free-field, standard ½” microphones fixed to the engine with glue, adhesive tape or mounted on a tripod.

  •                   Cumbersome and very time-consuming,
  •                   Setup is difficult to reproduce, the accuracy of the results is limited.

Solution: GRAS’ new solution is the 147AX microphone (patent pending) optimized to withstand the challenging conditions found in an engine bay. The new form factor and unique mounting system allow measurements in confined spaces and enable easy mounting. With the microphone, the ATF method can be improved significantly to ensure much greater repeatability and very fast test setup. Moreover, the same microphone can be used in the same test setup for both cold engine and on-road testing

  •                    Easy mounting
  •                    Time saving and better accuracy of results because of the set-up that can be closely reproduced

PDF: Acoustic Sensors for NVH Testing

Improving measurement procedure for engine noise reduction with advanced microphones

Video on 147AX