B&K Type 4206 Four-microphone Impedance Measurement Tube
This device is used to characterise the impedance and transmission loss properties of materials, in the frequency range of 50Hz-6.4kHz. Material samples with a diameter of 29mm and 100mm can be evaluated in the frequency range of 500Hz-6.4kHz and 50Hz-1.6kHz, respectively. The acoustic impedance and admittance are measured with this device. The sound absorption, reflection, and transmission loss coefficients are also obtained from this system.