This study aimed at estimating MOE of Boscia augustifolia wood using non-destructive longitudinal vibration acoustic method with the view to examining its reliability. Three trees of B. augustifolia were obtained, and samples of 20 × 20 × 300 mm 3 were collected for dynamic and static bending testing of the wood's elasticity. The samples were stored for a month prior testing after oven dried. Mean values of dynamic (dMOE) and static modulus of elasticity (sMOE) of B. augustifolia wood obtained were 6.908 ± 0.7525 GPa and 6.9148 ± 0.5870 GPa, respectively. Analysis done showed no significant difference between the values from the two methods while regression model was significant with 0.65 coefficient of determination. Strong correlation of 0.81 was observed between the dMOE and sMOE. Meanwhile, wood density had a correlation of 0.73 and 0.50 with dMOE and sMOE respectively. The acoustic method used was considered reliable for determining MOE of the wood.

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Acoustic test methods such as longitudinal vibration have been developed to predict the elastic properties of wood. However, attention has not been shifted to using this method to predict other mechanical properties, especially on Nigeria's preferred, and lesser-used wood species. Thus, we further investigate relationships among mechanical and acoustic properties of selected hardwood species with a view of predicting the mechanical properties of wood from acoustic parameters. Clear wood samples (324) of 20 by 20 by 20 mm3 were collected axially from Albizia adianthifolia, Gmelina arborea, Delonix regia, and Boscia anguistifolia trees, and conditioned before testing. The longitudinal vibration method was adopted to test for the dynamic (acoustic) parameters and properties (fundamental frequency, damping factor, dynamic modulus of elasticity, sound velocity, specific elastic modulus, radiation coefficient, acoustic conversion efficiency, acoustic impedance) while the universal testing machine was used to test for the mechanical properties (static modulus of elasticity, modulus of rupture, maximum compression strength parallel to grain). The damping factor, dynamic modulus of elasticity, and acoustic impedance were the best acoustic parameters that significantly correlated with the static modulus of elasticity (−0.57, 0.81, 0.76), modulus of rupture −0.64, 0.82, 0.85) and maximum compression strength parallel to grain (−0.52, 0.78, 0.84), respectively. There was a significant difference in the mechanical properties with respect to species, thus A. adianthifolia and G. arborea were mechanically better than D. regia and B. anguistifolia for construction or structural purposes. This study revealed that additional new acoustic measures are suitable for inferring mechanical wood properties.

This paper endeavoured to assess the acoustic properties of talking drums made from hourglass shells of different geometric shapes out of Gmelina arborea wood with the view of assessing and improving the acoustic properties of the talking drum. Talking drums from 6 different geometric shapes were manufactured from base wood of G. arborea. The lowest and highest means were 172.10 and 175.75 HZ for resonance frequency, 43.67 and 46.50 dB for amplitude, 635.00 and 743.33 ms for sound damping time, 0.06 and 0.14 for best timbre harmonic, 0.30 and 0.41 for poorest harmonic, respectively. Conclusively, talking drums made from these hourglass shells compared differently and it was found that hourglass shell making the talking drum and tension on the rope influences the drum's acoustic performance.

Wood is a unique material for making musical instruments and is used to make West African talking drums, whose pitch can be regulated depending upon how the player strikes the head of drum and changes its tension. Additionally, talking drum manufacturers have certain wood preferences, and in the absence of preferred species, they use supposedly unsuitable woods. Therefore, there is a need to examine wood traits in relation to the pitch of a talking drum. This study was designed to determine the existing relationship between selected wood traits and the frequency of talking drums made from A. robusta wood. Three A. robusta trees were obtained from Onigambari Forest Reserve. From each tree, three bolts of 50 cm in length were obtained from the base, middle, and top of the tree to determine selected properties (moisture content (MC), wood basic density (WBD), modulus of elasticity (MOE), modulus of rupture (MOR), and manufacturing of talking drums). A spectrum analyzer was used to analyze the sound frequency of the talking drums at three pitch levels (high, medium, low). A completely randomized block design was used and the data obtained was analyzed using descriptive statistics, ANOVA, and correlation analyses at α 0.05. Sound frequency was not significant along sampling height, but was significant at pitch levels. Additionally, the correlation analysis between wood traits and sound frequency was not significant. Thus, wood cannot be recommended for talking drums’ optimal acoustic performance based on wood traits alone.