We investigated the influence of the structure of wood on acoustic properties. We have visually selected planks of African padouk, black locust and maple woods and cut test specimens of smaller dimensions. We have graded the wood specimens into 5 acoustic quality grades by hearing examination and later measured the fundamental frequency and sound damping with elastic mechanical excitation and determined selected acoustic quality indicators. Visual assessment of raw wood quality matched closely to the measurements of the speed of sound along the grain and to the transverse specific modulus of elasticity. Grain angle and texture strongly affected the acoustic quality of African padouk, while density did not have a significant impact. We have reached similar grading between hearing examination and instrumental measurements of test specimens using damping coefficient (tan ) and relative acoustic conversion efficiency (RACE). While having similar average values of specific modulus of elasticity (E / ), African padouk returned lower damping coefficient than black locust or maple.
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