Focal Utopia Be 21 WX Woofer is a 21cm (8") subwoofer, Multiferrite magnet. 21 WX combines smaller dimensions and limited inner volume for deep, high-impact bass reproduction.

Specifications 

• Nominal impedance: 4 Ohms
• Product type: Subwoofer
• Frequency response (+/-3dB) depending on load: 29Hz - 500Hz
• Subwoofer: 21cm (8")
• Load volume: 15 - 30 litres (0.530 - 1.059 Ft³)
• Cut-out diameter: 182mm (7.2")
• Voice coil: 50mm (2")
• Magnet: Multiferrite (12 ferrites)
• Sensitivity (2.83V/1m): 86.5dB
• Nom. power: 250W
• Max. power: 500W
• Load: Sealed or vented
• Depth from wall: 106mm (4.2")