Classificação de madeiras da Amazônia para composição de instrumento musical de corda por meio da técnica de excitação por impulso

Abstract

Vibration technology is a technique for evaluating the elastic and acoustic properties of wood and can be used to classify woods that have characteristics similar to those traditionally used by Luthiers. The objective of this research was to define the range of variation of technological parameters to classify Amazonian timber species for the composition of string musical instruments. Characterization of xylem elements, apparent density and applied to the impulse excitation technique for modulus of elasticity, sound velocity, sound impedance, radiation coefficient and damping of traditional wood (spruce, maple, cedar and jacaranda) used in the confection Instruments on the top, bottom and side. The most commercialized species of wood were diagnosed in the municipality of Cruzeiro do Sul-AC. From the survey the four main species were selected and the properties of the wood were characterized in the same way as the traditional ones, including the evaluation of the basic density, retratibility and coefficient of anisotropy. The results showed that the traditional woods on the top have light color, medium texture, right grain, low density, low impedance, high elasticity, high sound velocity, high sound radiation and low damping. Already, the background and lateral features darker color, fine to medium texture, right to irregular grain, presence of figure, medium to high density, high elasticity, high impedance, high cushioning, low sound velocity and low sound radiation. It was concluded that the caroba and marupá species can be used for musical string instruments. The species muirapiranga, tauari and cedar to the bottom and lateral. The use of the longitudinal vibration technique in the technological characterization of the wood allowed us to obtain the values of the technological variables quickly, accurately and with later use of the sample. Enabling, classifying the Amazonian alternative species as woods with potential for composing musical string instruments.