B&C Speaker 8NDL51

• Sensitivity (1W, 1m, infinite baffle) SPL1W 91.3dB
• Frequency response 70 - 3000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 70Hz
• Mechanical quality factor QMS 5.88
• Electrical quality factor QES 0.51
• Total quality factor QTS 0.47

Large signal parameters

• Maximum linear excursion xmax 7mm
• Air volume displaced at xmax VD 154cm³
• Power handling P 200W
• Program power Pmax 400W

Voice Coil

• Nominal impedance Z 16Ω
• DC resistance RE 10.6Ω
• Inductance (1kHz) LE 0.6mH
• VC Diameter 51mm
• Winding height HVC 17mm
• Winding material Copper
• Former material Glass Fibre

Magnet

• Flux density B 1.05T
• Force factor Bl 15.2N/A
• Motor constant Bl/√RE 4.67N/√W
• Air gap height HAG 8mm
• Material Neodymium Inside Slug

Diaphragm

• Effective diameter 167mm
• Effective area SD 220cm²
• Moving mass MMS 26g
• Moving mass (without air load) MMD 23.5g
• Material Waterproof Both Sides

Suspensions

• Stiffness KMS 4.88N/mm
• Compliance CMS 205µm/N
• Equivalent volume to the compliance VAS 13.4L
• Mechanical resistance RMS 1.94N·s/m

Dimensions

• Nominal diameter 8″
• 200mm
• Overall diameter 225mm
• Baffle cutout diameter 187mm
• Overall depth 90mm
• Flange thickness 11mm
• Mounting depth 79mm
• Volume occupied by the driver 1.1L
• Net weight 1.85kg