Eighteen Sound 18ND9300

• Sensitivity (1W, 1m, infinite baffle) SPL1W 95.7dB
• Frequency response 28 - 2500Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 30Hz
• Mechanical quality factor QMS 7.86
• Electrical quality factor QES 0.29
• Total quality factor QTS 0.28

Large signal parameters

• Maximum linear excursion xmax 9.5mm
• Maximum excursion before damage xlim 25mm
• Air volume displaced at xmax VD 1159cm³
• Power handling P 1000W
• Program power Pmax 1400W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.0Ω
• Inductance (1kHz) LE 2.02mH
• VC Diameter 100mm
• Winding material Copper

Magnet

• Force factor Bl 24.4N/A
• Motor constant Bl/√RE 10.9N/√W
• Material Neodymium

Diaphragm

• Effective diameter 394mm
• Effective area SD 1220cm²
• Moving mass MMS 184g
• Moving mass (without air load) MMD 154g
• Material Straight ribbed carbon fiber loaded cellulose

Suspensions

• Stiffness KMS 6.67N/mm
• Compliance CMS 150µm/N
• Equivalent volume to the compliance VAS 316L
• Mechanical resistance RMS 4.41N·s/m
• Surround material Triple roll, Polycotton

Dimensions

• Nominal diameter 18″
• 460mm
• Overall diameter 462mm
• Baffle cutout diameter 422mm
• Overall depth 224mm
• Flange thickness 26mm
• Mounting depth 198mm
• Volume occupied by the driver (estimated) 5.3L
• Net weight 7.6kg