DB Drive Speed SPF10D4

• Sensitivity (1W, 1m, infinite baffle) SPL1W 82.6dB

Thiele & Small parameters

• Resonance frequency (free air) fS 27.4Hz
• Mechanical quality factor QMS 7.76
• Electrical quality factor QES 0.86
• Total quality factor QTS 0.74

Large signal parameters

• Power handling P 300W
• Program power Pmax 1000W

Voice Coil

• Nominal impedance Z 2 x 4Ω
• DC resistance (in series) RE 7.3Ω
• Inductance (1kHz, in series, estimated) LE 4.01mH
• VC Diameter 63.5mm
• Former material Aluminum

Magnet

• Force factor (in series) Bl 13.5N/A
• Motor constant Bl/√RE 4.98N/√W
• Material Ferrite

Diaphragm

• Effective diameter 210mm
• Effective area SD 346cm²
• Moving mass MMS 124g
• Moving mass (without air load) MMD 120g

Suspensions

• Stiffness KMS 3.69N/mm
• Compliance CMS 271µm/N
• Equivalent volume to the compliance VAS 46.1L
• Mechanical resistance RMS 2.76N·s/m
• Surround material Foam

Dimensions

• Nominal diameter 10″
• 254mm
• Overall diameter 265mm
• Baffle cutout diameter 230mm
• Mounting depth 89mm
• Volume occupied by the driver (estimated) 1.7L
• Frame material Steel