SB Acoustics SB12MNRX2-25-4

• Sensitivity (1W, 1m, infinite baffle) SPL1W 87.6dB

Thiele & Small parameters

• Resonance frequency (free air) fS 63.5Hz
• Mechanical quality factor QMS 4.19
• Electrical quality factor QES 0.35
• Total quality factor QTS 0.32

Large signal parameters

• Maximum linear excursion xmax 2.2mm
• Air volume displaced at xmax VD 11cm³
• Power handling P 50W
• Program power Pmax 100W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.2Ω
• Inductance (1kHz) LE 0.15mH
• VC Diameter 25.4mm
• Winding height HVC 9.4mm
• Winding material Copper Clad Aluminium
• Former material Glass Fiber

Magnet

• Flux density B 1.03T
• Force factor Bl 3.9N/A
• Motor constant Bl/√RE 2.18N/√W
• Air gap height HAG 5mm
• Weight 0.4kg

Diaphragm

• Effective diameter 80mm
• Effective area SD 50cm²
• Moving mass MMS 4.2g
• Moving mass (without air load) MMD 3.9g
• Material Norex

Suspensions

• Stiffness KMS 0.667N/mm
• Compliance CMS 1500µm/N
• Equivalent volume to the compliance VAS 5.3L
• Mechanical resistance RMS 0.4N·s/m
• Surround material Butyl rubber

Dimensions

• Nominal diameter 4″
• 102mm
• Volume occupied by the driver (estimated) 0.36L
• Net weight 0.92kg
• Frame material Cast aluminium