Eighteen Sound 15NTLS3500

• Sensitivity (1W, 1m, infinite baffle) SPL1W 89.7dB
• Frequency response 30 - 2000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 28Hz
• Mechanical quality factor QMS 8.20
• Electrical quality factor QES 0.44
• Total quality factor QTS 0.42

Large signal parameters

• Maximum linear excursion xmax 15.3mm
• Air volume displaced at xmax VD 1348cm³
• Power handling P 950W
• Program power Pmax 1900W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.2Ω
• Inductance (1kHz) LE 1.65mH
• VC Diameter 88mm
• Winding height HVC 36mm
• Winding material Copper

Magnet

• Force factor Bl 21.6N/A
• Motor constant Bl/√RE 9.47N/√W
• Air gap height HAG 11mm
• Material Neodymium

Diaphragm

• Effective diameter 335mm
• Effective area SD 881cm²
• Moving mass MMS 250g
• Moving mass (without air load) MMD 232g
• Material Weather protected

Suspensions

• Stiffness KMS 6.94N/mm
• Compliance CMS 144µm/N
• Equivalent volume to the compliance VAS 141L
• Mechanical resistance RMS 5.36N·s/m
• Surround material Rubber

Dimensions

• Nominal diameter 15″
• 393mm
• Overall diameter 393mm
• Baffle cutout diameter 357mm
• Overall depth 261mm
• Flange thickness 17mm
• Mounting depth 244mm
• Volume occupied by the driver (estimated) 5.6L
• Net weight 8.3kg