Recently, an array of PCB model T130D21 microphones, available from Biolab , was used to evaluate the noise sources on a vacuum cleaner running at different frequencies. An articulating conformal array and software system not only reduced the setup time for near-field measurements but identified the true noise sources on the product, both structure and airborne.
It would seem that the source of the noise would be from the vacuum cleaner motor or suction hose, but depending upon the frequency, the results proved that the dirt storage container was the main source of noise at specific frequencies. By redesigning the container, the manufacturer was able to reduce the overall noise of the vacuum cleaner, thus providing their customers a desirable product.
PCB model T130D21 array microphones, with their good phase characteristics, were selected to detect the sound source. Using an array of these microphones minimises the number of samples needed and thus shortens set-up and test time, saving valuable time and money by running a complex test only once. PCB array microphones are small, cost effective and are suitable for performing the same type of testing on a variety of products ranging from electric razors to car doors.