Eighteen Sound 12ND830 8Ω

• Sensitivity (1W, 1m, infinite baffle) SPL1W 97dB
• Frequency response 53 - 5000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 55Hz
• Mechanical quality factor QMS 5.15
• Electrical quality factor QES 0.30
• Total quality factor QTS 0.28

Large signal parameters

• Maximum linear excursion xmax 6.5mm
• Air volume displaced at xmax VD 345cm³
• Power handling P 450W
• Program power Pmax 700W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.7Ω
• Inductance (1kHz) LE 1.5mH
• VC Diameter 75mm
• Winding material Aluminum

Magnet

• Force factor Bl 17.6N/A
• Motor constant Bl/√RE 7.37N/√W
• Material Neodymium

Diaphragm

• Effective diameter 260mm
• Effective area SD 531cm²
• Moving mass MMS 46g
• Moving mass (without air load) MMD 37.2g
• Material Weather protected

Suspensions

• Stiffness KMS 5.5N/mm
• Compliance CMS 182µm/N
• Equivalent volume to the compliance VAS 72L
• Mechanical resistance RMS 3.09N·s/m

Dimensions

• Nominal diameter 12″
• 300mm
• Overall diameter 315mm
• Baffle cutout diameter 282mm
• Overall depth 140mm
• Flange thickness 9mm
• Mounting depth 131mm
• Volume occupied by the driver (estimated) 2.1L
• Net weight 4.3kg