Ceiling speaker in wall speaker series bose virtually invisible system 2 way system speaker system 20 stereo recommended amplifier power 10 100 speaker enclosures removable speaker cover without casing number of tweeters 2 treble chassis 19 mm number of subwoofers 1 bass chassis 127 mm width 206 mm height 206 mm depth 104 mm weight 14 kg area of use home cinema hifi system living room installation options ceiling mount