Normal Incidence of Sound Transmission Loss of a Double-Leaf Partition Inserted with a Microperforated Panel

Figure 4

Comparison of sound transmission loss of DL (—) with that of DL-MPP for different hole diameters (𝑙=0.1𝐷, 𝜎=1.5%, 𝐷=100 mm; ··· 𝑑_𝑜=0.1 mm, – · – 𝑑_𝑜=0.2 mm, and – – 𝑑_𝑜=0.4 mm).