B&C Speaker 21SW115

• Sensitivity (1W, 1m, infinite baffle) SPL1W 95.1dB
• Frequency response 33 - 1000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 33Hz
• Mechanical quality factor QMS 7.70
• Electrical quality factor QES 0.37
• Total quality factor QTS 0.36

Large signal parameters

• Maximum linear excursion xmax 14mm
• Air volume displaced at xmax VD 2352cm³
• Power handling P 1700W
• Program power Pmax 3400W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.6Ω
• Inductance (1kHz) LE 1.7mH
• VC Diameter 116mm
• Winding height HVC 34mm
• Winding material Copper
• Former material Glass Fibre

Magnet

• Flux density B 1.15T
• Force factor Bl 24.8N/A
• Motor constant Bl/√RE 13.1N/√W
• Air gap height HAG 14mm
• Material Neodymium Inside Slug

Diaphragm

• Effective diameter 462mm
• Effective area SD 1680cm²
• Moving mass MMS 335g
• Moving mass (without air load) MMD 287g
• Material Waterproof Both Sides

Suspensions

• Stiffness KMS 13.2N/mm
• Compliance CMS 76µm/N
• Equivalent volume to the compliance VAS 278L
• Mechanical resistance RMS 9.02N·s/m
• Spider material Silicone

Dimensions

• Nominal diameter 21″
• 530mm
• Overall diameter 547mm
• Baffle cutout diameter 503mm
• Overall depth 249mm
• Flange thickness 14mm
• Mounting depth 235mm
• Volume occupied by the driver 15L
• Net weight 14.0kg