Usability of particle board as well as other wood composites is very wide. They can be used in furniture industry as well as in the construction industry, where in addition to mechanical and sorption properties, acoustic are also important. Acoustic properties are influenced by the board density which can be changed by using different wood species, and also by changing the ratio between surface and core layer. We wanted to find out how changing the proportion of surface/core layer effects the absorption of sound and what the role of each layer is. In laboratory conditions we made 3 particle boards, different regarding to core layer share (30 %, 45 % and 60 %). Measurements were performed using REW V5 programme, a Java application for measuring room acoustics and analysing room and loudspeaker responses, including tools for generating test signals, measuring SPL (Sound Pressure Level), impedance, etc. The measurements show that the sound absorption is mainly affected by the surface layer, built with the finest particles having a larger specific area than bigger particles within the core layer of 3-layeredboard, and therefore greater ability to absorb sound. We also found that the absorption of sound at higher frequencies is higher at the core layer of plates than the plates with smaller amount of surface layer.
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