Dayton Audio Odeum Apollo 18N

• Sensitivity (1W, 1m, infinite baffle) SPL1W 95.6dB
• Frequency response 35 - 1000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 32Hz
• Mechanical quality factor QMS 10.02
• Electrical quality factor QES 0.35
• Total quality factor QTS 0.33

Large signal parameters

• Maximum linear excursion xmax 9.1mm
• Air volume displaced at xmax VD 1092cm³
• Power handling P 1200W
• Program power Pmax 2400W

Voice Coil

• Nominal impedance Z 8Ω
• DC resistance RE 6.1Ω
• Inductance (1kHz) LE 0.61mH
• VC Diameter 101.6mm
• Winding material Copper
• Former material Glass Fiber

Magnet

• Force factor Bl 27.6N/A
• Motor constant Bl/√RE 11.2N/√W
• Material Neodymium

Diaphragm

• Effective diameter 391mm
• Effective area SD 1200cm²
• Moving mass MMS 218g
• Moving mass (without air load) MMD 189g
• Material Coated paper

Suspensions

• Stiffness KMS 8.77N/mm
• Compliance CMS 114µm/N
• Equivalent volume to the compliance VAS 254L
• Mechanical resistance RMS 4.37N·s/m
• Surround material Paper

Dimensions

• Nominal diameter 18″
• 462mm
• Overall diameter 462mm
• Baffle cutout diameter 414mm
• Overall depth 184mm
• Volume occupied by the driver (estimated) 5.7L
• Frame material Steel