Eighteen Sound 12NTLW3500

• Sensitivity (1W, 1m, infinite baffle) SPL1W 94.6dB
• Frequency response 50 - 3000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 54Hz
• Mechanical quality factor QMS 13.10
• Electrical quality factor QES 0.34
• Total quality factor QTS 0.33

Large signal parameters

• Maximum linear excursion xmax 8.3mm
• Air volume displaced at xmax VD 441cm³
• Power handling P 900W
• Program power Pmax 1800W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.1Ω
• Inductance (1kHz) LE 0.29mH
• VC Diameter 88mm
• Winding material Aluminum

Magnet

• Force factor Bl 16.3N/A
• Motor constant Bl/√RE 9.26N/√W
• Material Neodymium

Diaphragm

• Effective diameter 260mm
• Effective area SD 531cm²
• Moving mass MMS 85g
• Moving mass (without air load) MMD 76.4g

Suspensions

• Stiffness KMS 9.8N/mm
• Compliance CMS 102µm/N
• Equivalent volume to the compliance VAS 41L
• Mechanical resistance RMS 2.2N·s/m

Dimensions

• Nominal diameter 12″
• 300mm
• Overall diameter 310mm
• Baffle cutout diameter 282mm
• Overall depth 193mm
• Flange thickness 13mm
• Mounting depth 180mm
• Volume occupied by the driver (estimated) 2.7L
• Net weight 4.7kg