BishopSound BWN21/4

• Sensitivity (1W, 1m, infinite baffle) SPL1W 95.2dB
• Frequency response 33 - 1000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 33Hz
• Mechanical quality factor QMS 6.20
• Electrical quality factor QES 0.36
• Total quality factor QTS 0.35

Large signal parameters

• Maximum linear excursion xmax 14mm
• Maximum excursion before damage xlim 15.3mm
• Air volume displaced at xmax VD 2282cm³
• Power handling P 2000W
• Program power Pmax 4000W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.6Ω
• Inductance (1kHz) LE 1.7mH
• VC Diameter 125mm
• Winding height HVC 34mm
• Winding material Copper
• Former material Glass Fiber

Magnet

• Flux density B 1.2T
• Force factor Bl 25.2N/A
• Motor constant Bl/√RE 13.3N/√W
• Air gap height HAG 14mm
• Material Ferrite Ring

Diaphragm

• Effective diameter 456mm
• Effective area SD 1630cm²
• Moving mass MMS 330g
• Moving mass (without air load) MMD 283g

Suspensions

• Stiffness KMS 12.5N/mm
• Compliance CMS 80µm/N
• Equivalent volume to the compliance VAS 263L
• Mechanical resistance RMS 5.21N·s/m

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 18L
• Net weight 18.0kg
• Frame material Aluminium