JBL SUB18 Passive 18" Studio SubwooferJBL introduces its most powerful studio subwoofer for applications in which very high continuous output and extreme low frequency response is required. With in room response below 18Hz and 137 dB peak output, the SUB18 delivers unprecedented performance for demanding dance music production, while providing exceptional accuracy required in cinema post production applications. As an add on to JBL's M2 Master Reference Monitor system, the SUB18 allows