Eighteen Sound 15ND730

• Sensitivity (1W, 1m, infinite baffle) SPL1W 97.7dB
• Frequency response 44 - 4000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 44Hz
• Mechanical quality factor QMS 8.10
• Electrical quality factor QES 0.30
• Total quality factor QTS 0.29

Large signal parameters

• Maximum linear excursion xmax 6.5mm
• Air volume displaced at xmax VD 585cm³
• Power handling P 400W
• Program power Pmax 600W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.5Ω
• Inductance (1kHz) LE 1.35mH
• VC Diameter 75mm

Magnet

• Force factor Bl 21N/A
• Motor constant Bl/√RE 8.95N/√W
• Material Neodymium

Diaphragm

• Effective diameter 339mm
• Effective area SD 900cm²
• Moving mass MMS 86g
• Moving mass (without air load) MMD 67.7g
• Material Weather protected

Suspensions

• Stiffness KMS 6.58N/mm
• Compliance CMS 152µm/N
• Equivalent volume to the compliance VAS 156L
• Mechanical resistance RMS 2.94N·s/m

Dimensions

• Nominal diameter 15″
• 380mm
• Overall diameter 387mm
• Baffle cutout diameter 353mm
• Overall depth 169mm
• Flange thickness 11mm
• Mounting depth 158mm
• Volume occupied by the driver (estimated) 2.6L
• Net weight 3.9kg