Rockford Fosgate R1S4-12

• Sensitivity (1W, 1m, infinite baffle) SPL1W 88.4dB

Thiele & Small parameters

• Resonance frequency (free air) fS 30.5Hz
• Mechanical quality factor QMS 7.97
• Electrical quality factor QES 0.58
• Total quality factor QTS 0.54

Large signal parameters

• Maximum linear excursion xmax 7mm
• Air volume displaced at xmax VD 372cm³
• Power handling P 200W
• Program power Pmax 400W

Voice Coil

• Nominal impedance Z 4Ω
• DC resistance RE 3.5Ω
• Inductance (1kHz) LE 2.1mH
• VC Diameter 51mm

Magnet

• Force factor Bl 11.8N/A
• Motor constant Bl/√RE 6.31N/√W
• Weight 1.13kg

Diaphragm

• Effective diameter 260mm
• Effective area SD 531cm²
• Moving mass MMS 121g
• Moving mass (without air load) MMD 112g

Suspensions

• Stiffness KMS 4.43N/mm
• Compliance CMS 226µm/N
• Equivalent volume to the compliance VAS 90.4L
• Mechanical resistance RMS 2.9N·s/m

Dimensions

• Nominal diameter 12″
• 319mm
• Overall diameter 319mm
• Baffle cutout diameter 285mm
• Mounting depth 125mm
• Volume occupied by the driver 2.83L