Abstract: This engineering brief describes the design, construction and validation of a low-cost acoustic anechoic chamber. This anechoic chamber will be used in a production setting as well as for research and development of a microphone array system. Three chambers have been built using the same method. The performance of the rooms is evaluated in terms of sound isolation, deviation from inverse square law, frequency response function and reverberation time. Results show that in the frequency range of interest (250 - 11025 Hz), the reverberation time for the three chambers is 19 ± 3 ms. The difference between the frequency response of the chambers is ± 4 dB in the frequency range of interest for the two latest built chambers, whereas the first chamber shows a larger deviation.