Effects of the absorber location on low-frequency noise control in typical dwelling layouts

Abstract Studies on the effects of absorber location on low-frequency noise control in acoustically coupled rooms have been limited. This study investigated the effects of the absorption area and location on low-frequency noise control in typical dwelling layouts for different room connection types. In-situ measurements under a steady-state noise showed significant results in rooms with an absorber. An absorption area of only 5–6 m2 in the bedroom, wherein noise enters first, was equivalent to an area of 22.5 m2 in the bedroom farthest from the sound source. Noise reduction generally increased by 0.3–0.5 dB/m2 within 7.5 m2 absorption area, and later increased by less than 0.2 dB/m2 or became overdamped. Moreover, the standard deviation of the sound pressure level (loud–quiet difference) increased with the absorption area in the living room, while it decreased in the bedroom oriented to the sound source. Noise reduction was constantly high (approximately 6–7 dB) when the absorption area distribution proportion between the living room and the bedroom oriented to the sound source was within 1:5–5:1. Further, the optimal and worst absorber locations were also suggested to ensure a low-frequency noise control in the layouts.