Eighteen Sound 12ND930

• Sensitivity (1W, 1m, infinite baffle) SPL1W 97dB
• Frequency response 46 - 4500Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 50Hz
• Mechanical quality factor QMS 5.64
• Electrical quality factor QES 0.22
• Total quality factor QTS 0.21

Large signal parameters

• Maximum linear excursion xmax 6.5mm
• Air volume displaced at xmax VD 345cm³
• Power handling P 500W
• Program power Pmax 800W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.5Ω
• Inductance (1kHz) LE 1.65mH
• VC Diameter 75mm
• Winding material Copper

Magnet

• Force factor Bl 21.2N/A
• Motor constant Bl/√RE 9.04N/√W
• Material Neodymium

Diaphragm

• Effective diameter 260mm
• Effective area SD 531cm²
• Moving mass MMS 57g
• Moving mass (without air load) MMD 48.2g

Suspensions

• Stiffness KMS 5.62N/mm
• Compliance CMS 178µm/N
• Equivalent volume to the compliance VAS 70L
• Mechanical resistance RMS 3.18N·s/m

Dimensions

• Nominal diameter 12″
• 300mm
• Overall diameter 315mm
• Baffle cutout diameter 282mm
• Overall depth 140mm
• Flange thickness 11mm
• Mounting depth 129mm
• Volume occupied by the driver (estimated) 2.2L
• Net weight 4.4kg