Outdoor speaker series yamaha performance yamaha ns power rating 40 watt system 2 way system principle passive frequency response 60 25000 hz sensitivity 86 dbmw impedance 6 ohm power supply passive colour white protective properties weather resistant speaker enclosure closed number of tweeters 1 treble chassis 20 mm number of midbass drivers 1 bassmidtone chassis 130 mm width 170 mm height 273 mm depth 136 mm weight 18 kg area o