Eighteen Sound 18NLW4500 8Ω

• Sensitivity (1W, 1m, infinite baffle) SPL1W 94.2dB
• Frequency response 30 - 1000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 35Hz
• Mechanical quality factor QMS 9.70
• Electrical quality factor QES 0.34
• Total quality factor QTS 0.33

Large signal parameters

• Maximum linear excursion xmax 15.3mm
• Air volume displaced at xmax VD 1874cm³
• Power handling P 1800W
• Program power Pmax 3600W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.0Ω
• Inductance (1kHz) LE 2mH
• VC Diameter 115mm
• Winding material Copper

Magnet

• Force factor Bl 30.3N/A
• Motor constant Bl/√RE 13.6N/√W

Diaphragm

• Effective diameter 395mm
• Effective area SD 1225cm²
• Moving mass MMS 286g
• Moving mass (without air load) MMD 256g

Suspensions

• Stiffness KMS 13.9N/mm
• Compliance CMS 72µm/N
• Equivalent volume to the compliance VAS 151L
• Mechanical resistance RMS 6.48N·s/m

Dimensions

• Nominal diameter 18″
• 462mm
• Overall diameter 462mm
• Baffle cutout diameter 422mm
• Overall depth 233mm
• Flange thickness 23mm
• Mounting depth 210mm
• Volume occupied by the driver (estimated) 7.3L
• Net weight 12.0kg