Details:

New Natural Sound 5.1-channel speaker package
2-Way, dual woofer speakers with silk dome tweeter
Wall-mountable speakers
Magnetic shielding (all speakers)
Removable grille [front, center and surround]
8" 100W subwoofer with Advanced Yamaha Active Servo Technology II for deep, powerful bass
Specifications

Speakers Type 2-Way Acoustic Suspension
Speakers 2-1/2" woofer x 2, 3/4" silk dome tweeter
Frequency Range 100Hz - 35kHz
Impedance 6 ohms
Nominal Input 30 W
Maximum Input 100 W
Sensitivity 82dB/2.83 V/m
Crossover Frequency 4 kHz
Removable Grilles Yes
Magnetic Shielding Yes
Speakers Dimensions (W x H x D) Main and Surround Speakers: 10-1/8 x 3-5/8 x 4-3/8, Center Speaker: 3-5/8 x 10-1/8 x 4-3/8
Weight Main and Surround Speakers: 3.09 lbs., Center Speaker: , 2.98 lbs.
Subwoofer Type Advanced Yamaha Active Servo Technology II
Driver 8" cone woofer (Magnetically shielded type)
Subwoofer Output Power 50 W
Subwoofer Dynamic Power 100 W
Subwoofer Frequency Response 28 Hz  200 Hz
Subwoofer Input Sensitivity 50 mV (50 Hz, 50 W/5ohms)
Power Consumption 45 W
Subwoofer Dimensions (W x H x D) 11-3/8 x 11-3/8 x 12-7/8
Weight 18-3/4 lbs.
Shipping Dimensions (W x H x D) 24-1/4" x 15-1/4" x 22-3/8"