Eighteen Sound 6M44

• Sensitivity (1W, 1m, infinite baffle) SPL1W 92.9dB
• Frequency response 140 - 7000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 102Hz
• Mechanical quality factor QMS 4.40
• Electrical quality factor QES 0.31
• Total quality factor QTS 0.29

Large signal parameters

• Maximum linear excursion xmax 2.3mm
• Air volume displaced at xmax VD 30cm³
• Power handling P 200W
• Program power Pmax 350W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 5.3Ω
• Inductance (1kHz) LE 0.32mH
• VC Diameter 44mm
• Winding height HVC 8mm
• Winding material Aluminum

Magnet

• Force factor Bl 13.4N/A
• Motor constant Bl/√RE 5.82N/√W
• Air gap height HAG 7mm
• Material Ferrite

Diaphragm

• Effective diameter 130mm
• Effective area SD 132cm²
• Moving mass MMS 16g
• Moving mass (without air load) MMD 14.9g
• Material Weather protected

Suspensions

• Stiffness KMS 6.58N/mm
• Compliance CMS 152µm/N
• Equivalent volume to the compliance VAS 3.8L
• Mechanical resistance RMS 2.33N·s/m

Dimensions

• Nominal diameter 6.5″
• 162mm
• Overall diameter 162mm
• Baffle cutout diameter 148mm
• Overall depth 85mm
• Flange thickness 13mm
• Mounting depth 72mm
• Volume occupied by the driver (estimated) 0.87L
• Net weight 3.4kg