We investigated whether there is a relationship between the emitted sound impact and hardness of woods and solid wood flooring. In this study we examined test pieces of spruce, larch, oak, beech and ash wood, the nominal thickness of 20 mm. Hardness of wood was determined by standard Brinell method and by dynamic method using dropping of the steel ball, in which the acoustic response was measured. We have found increase of the wood hardness by increasing the density of the wood species. We have confirmed also the correlation of the size of wood surface damage at the dynamic method measurement with the indentation diameter at the standard Brinell method. By increasing of surface damage at the fall of steel ball the decrease of measured maximal-, exponential average- and the average sound pressure level was confirmed. The frequency range of the measured sound spectrum was greater at soft wood species. The results suggest using of soft wood species for silent spaces to decrease the emitted impact noise.
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