Impedance & transmission tube using 4 microphones
Mecanum’s 4 microphones impedance tubes are specifically designed to measure the main normal indicators of a wide range of acoustical materials. The method is based on ASTM E1050, ISO 10534-2 and ASTM E2611 standards for the absorption coefficient (α), the reflection coefficient (R) and the surface impedance (Zs). All other parameters are determined using the 4 microphones technique (ASTM E2611) or the 3 microphones technique12.
Note: All 4 microphones tubes also comes with the 3 microphones technique, in other words, all the latest techniques and standards are gathered in this high-end equipment.
** Large spacing between µ1 and µ2 (or µ3 and µ4) is essential for better results at low frequencies (as stated in ASTM E1050)
➡ Transfer matrix coefficients (Tij)
|Tube Internal Diameter||Frequency Range|
|29 mm||200-6600 Hz|
|44.44 mm||100-4300 Hz|
|100 mm||35-1900 Hz|
Tube-X is a user-friendly software that will simplify your measurement procedure. It will allow you to choose between the different measurement techniques. It’s also fully compatible with Foam-X software that can extract non-acoustic parameters of porous materials using the inverse method with a 2, 3 or 4 microphones absorption measurement and indirect method using the 3 or 4 microphones measurement.
- Every Mecanum impedance tube is supplied with grids (for samples with low mechanical strength) and rings (to avoid leaks).
- Different accessories may be used with impedance tubes according to your needs.