Characterization of Sound Absorption Coefficient and Acoustic Impedance of Palm Frond Fiber Composites with Pine Resin on Various Composition Variations. JTM [Internet]. 2023 Apr. 30 [cited 2026 Feb. 27];13(1):6-12. Available from: https://jtm.itp.ac.id/index.php/jtm/article/view/725