Skar Audio SDR-8 D4

• Sensitivity (1W, 1m, infinite baffle) SPL1W 83.1dB

Thiele & Small parameters

• Resonance frequency (free air) fS 39Hz
• Mechanical quality factor QMS 5.10
• Electrical quality factor QES 0.68
• Total quality factor QTS 0.61

Large signal parameters

• Maximum linear excursion xmax 8.8mm
• Air volume displaced at xmax VD 177cm³
• Power handling P 350W
• Program power Pmax 700W

Voice Coil

• Nominal impedance Z 2 x 4Ω
• DC resistance (in series) RE 8.4Ω
• Inductance (1kHz, in series, estimated) LE 3.23mH
• VC Diameter 50.8mm
• Winding material Copper

Magnet

• Force factor (in series) Bl 14.7N/A
• Motor constant Bl/√RE 5.07N/√W
• Diameter 134mm

Diaphragm

• Effective diameter 160mm
• Effective area SD 201cm²
• Moving mass MMS 72.8g
• Moving mass (without air load) MMD 70.6g
• Material Pressed Paper

Suspensions

• Stiffness KMS 8.2N/mm
• Compliance CMS 122µm/N
• Equivalent volume to the compliance VAS 6.98L
• Mechanical resistance RMS 3.5N·s/m
• Surround material Foam

Dimensions

• Nominal diameter 8″
• 214mm
• Overall diameter 214mm
• Baffle cutout diameter 183mm
• Overall depth 137mm
• Flange thickness 18mm
• Mounting depth 119mm
• Volume occupied by the driver (estimated) 1.4L