The Yamaha NS-SP1800BL 5.1-channel home theater speaker package is a low cost, convenient way to enjoy the full benefits of 5.1-channel home theater sound. The NS-SP1800BL features advanced Yamaha Active Servo Technology (Advanced YST), which is a unique system in which the speaker and amplifier work together to cancel out impedance so the speaker unit has a perfectly linear motion. Advanced YST helps to ensure the highest levels of sound pressure and overall performance.Dimensions: Front Speaker: 4 x 6.3 x 4″ (100 x 160 x 100mm), Center Speaker: 11.9 x 4 x 4″ (300 x 100 x 100mm), Surround Speaker: 4 x 6.3 x 4″ (100 x 160 x 100mm), Sub woofer: 11.4 x 11.4 x 12.7″ (290 x 290 x 328mm).What’s in the box: Yamaha NS-SP1800BL 5.1-Channel Home
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