Oberton 8NM250 V2

• Sensitivity (1W, 1m, infinite baffle) SPL1W 98.1dB
• Frequency response 100 - 5000Hz

Thiele & Small parameters

• Resonance frequency (free air) fS 67.7Hz
• Mechanical quality factor QMS 13.94
• Electrical quality factor QES 0.26
• Total quality factor QTS 0.25

Large signal parameters

• Maximum linear excursion xmax 4mm
• Air volume displaced at xmax VD 81cm³
• Power handling P 250W
• Program power Pmax 500W

Voice Coil

• Nominal impedance Z 16Ω
• DC resistance RE 11.0Ω
• Inductance (1kHz) LE 0.27mH
• VC Diameter 64mm
• Winding height HVC 10mm
• Winding material Aluminium
• Former material Glass fiber

Magnet

• Flux density B 1.55T
• Force factor Bl 21.3N/A
• Motor constant Bl/√RE 6.42N/√W
• Air gap height HAG 7mm
• Material Neodymium

Diaphragm

• Effective diameter 160mm
• Effective area SD 202cm²
• Moving mass MMS 16.8g
• Moving mass (without air load) MMD 14.6g
• Material Paper with carbone fiber

Suspensions

• Stiffness KMS 6.66N/mm
• Compliance CMS 150µm/N
• Equivalent volume to the compliance VAS 8.39L
• Mechanical resistance RMS 0.51N·s/m

Dimensions

• Nominal diameter 8″
• 210mm
• Overall diameter 225mm
• Baffle cutout diameter 187mm
• Overall depth 84mm
• Volume occupied by the driver (estimated) 0.91L
• Net weight 2.7kg
• Frame material Die cast aluminium