Table 7.

Result from one-way ANOVA: effect of material composition (MC) on dB difference for 10,000 Hz frequency.

Material Composition (MC)	Additive	Mean dB Difference	Standard Deviation	Significance (p-Value)
Glass fiber (G-G-G)	Palm fiber	28.4	0.7	p < 0.05
Glass fiber (G-G-G)	Coffee husk	31.0	0.5	p < 0.05
Glass fiber (G-G-G)	None	19.9	0.8	p < 0.05
Jute fiber (J-J-J)	Palm fiber	44.9	1.2	p < 0.01
Jute fiber (J-J-J)	Coffee husk	41.8	0.9	p < 0.01
Jute fiber (J-J-J)	None	29.6	1.1	p < 0.05
Hybrid (G-J-G)	Palm fiber	35.9	0.9	p < 0.05
Hybrid (G-J-G)	Coffee husk	34.6	1.0	p < 0.05
Hybrid (G-J-G)	None	25.4	1.2	p < 0.05