TS-828S Professional Speaker Datasheet Manual Firmware FeatureAdopt the 18″ subwoofer unit.18mm birch housing, light weight, wear-resistant spray paint treatment, and dust-proof net cotton inside.Large inverter hole can reduce the distortion degree.There is a jack at the top for mounting a column with a diameter of 35mm.Specification:ModelTS-828SImpedance4ΩFrequency response40Hz-400HzRated power1200WPeak power4800WSensitivity100dB/W/MMaximum SPL (rated/peak)131dB/138dBBass18″bass×2Dimension (HxWxD)540x1164x760 mmWeight85Kg