Investigation of sound absorption for various types of yarn

Sound absorption properties of certain yarns are investigated with the aim to find new selection of materials for sound insulation purposes. Acoustic measurements of sound absorption on samples of cotton, wool and viscose yarns are done. The measurements are performed employing a tube method, on Brill & Kjaer (Copenhagen) equipment. Sound absorption measurements are performed in the frequency range from 160 to 5000 Hz, and sound absorption coefficient for each yam at various package densities determined. Packages of various densities are prepared in a volume, in a parallel (=) or a heterogenous (#) position. Sound absorption coefficients in a frequency range, for yarns of a definite raw material composition, density, fineness and in a definite position in relation to one another are represented by frequency characteristics of the coefficients. They clearly show that sound absorption coeficient is dependent upon all the above described yam package properties.