To accomplish preferred acoustic performance amounts, many interlayer components and glass styles could be used. Having said that, the addition of the 2nd pane of ordinary glass improves the STC performance as compared to solitary-pane glass. This is largely due to the air gap, which is a great acoustic insulator. https://acousticlaminatedglass55820.thenerdsblog.com/44855473/acoustic-laminated-glass-fundamentals-explained