Eighteen Sound 15ND930 8Ω

• Sensitivity (1W, 1m, infinite baffle) SPL1W 97.1dB
• Frequency response 40 - 4100Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 36Hz
• Mechanical quality factor QMS 5.30
• Electrical quality factor QES 0.23
• Total quality factor QTS 0.22

Large signal parameters

• Maximum linear excursion xmax 7.5mm
• Air volume displaced at xmax VD 638cm³
• Power handling P 500W
• Program power Pmax 800W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.5Ω
• Inductance (1kHz) LE 1.61mH
• VC Diameter 75mm
• Winding material Copper

Magnet

• Force factor Bl 23.8N/A
• Motor constant Bl/√RE 10.1N/√W
• Material Neodymium

Diaphragm

• Effective diameter 329mm
• Effective area SD 850cm²
• Moving mass MMS 101g
• Moving mass (without air load) MMD 83.7g
• Material Weather protected

Suspensions

• Stiffness KMS 5.16N/mm
• Compliance CMS 194µm/N
• Equivalent volume to the compliance VAS 206L
• Mechanical resistance RMS 4.31N·s/m

Dimensions

• Nominal diameter 15″
• 380mm
• Overall diameter 387mm
• Baffle cutout diameter 353mm
• Overall depth 177mm
• Flange thickness 11mm
• Mounting depth 166mm
• Volume occupied by the driver (estimated) 3L
• Net weight 4.7kg