Isicabha sokunciphisa umsindo ngokuvamile senziwe ngezinto eziminyene kakhulu, eziqinile.Lezi zinto eziminyene, eziqinile nazo zisebenza kahle ekubuyiseleni umsindo emthonjeni wawo.
Ikhono lesicabha lokunciphisa umsindo libizwa ngokuthi ukusebenza kahle kwawo kokudluliselwa komsindo (TL).Uma i-TL iphezulu, umphumela uba ngcono.
Izilinganiso zekilasi lokudluliswa komsindo (STC) zixazulula leyo nkinga ngokunikeza inani elilodwa ekusebenzeni kwe-acoustical yomnyango.Ukuphakama kwevelu ye-STC, izinga lokulinganisa lingcono kanye nokusebenza okungcono.