Eighteen Sound 12ND730

• Sensitivity (1W, 1m, infinite baffle) SPL1W 96.3dB
• Frequency response 53 - 5000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 45Hz
• Mechanical quality factor QMS 5.13
• Electrical quality factor QES 0.24
• Total quality factor QTS 0.23

Large signal parameters

• Maximum linear excursion xmax 6.5mm
• Air volume displaced at xmax VD 345cm³
• Power handling P 400W
• Program power Pmax 600W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.6Ω
• Inductance (1kHz) LE 1.73mH
• VC Diameter 75mm
• Winding material Copper

Magnet

• Force factor Bl 19.2N/A
• Motor constant Bl/√RE 8.11N/√W
• Material Neodymium

Diaphragm

• Effective diameter 260mm
• Effective area SD 531cm²
• Moving mass MMS 55g
• Moving mass (without air load) MMD 46.2g
• Material Weather protected

Suspensions

• Stiffness KMS 4.41N/mm
• Compliance CMS 227µm/N
• Equivalent volume to the compliance VAS 90L
• Mechanical resistance RMS 3.03N·s/m

Dimensions

• Nominal diameter 12″
• 300mm
• Overall diameter 315mm
• Baffle cutout diameter 282mm
• Overall depth 132mm
• Flange thickness 11mm
• Mounting depth 121mm
• Volume occupied by the driver (estimated) 1.9L
• Net weight 3.8kg