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SB Acoustics SB15SFCR39-4 5x8" Racetrack Midwoofer

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The SB Acoustics SB15SFCR39-4 is a unique 5x8 inch 'racetrack' style midwoofer featuring a robust vented steel chassis and a hard paper cone. This 4 ohm drive unit has that lovely warm, fast paper cone sound with good bass weight. Ideal for tall slim cabinets. Fantastic value.

Also available in 8 ohms: SB15SFCR39-8.

A matching passive radiator is available: SB15SFCR39-0

Key Features:

  • Space saving racetrack style design.
  • Hard paper cone (made in-house).
  • Optimized motor system.
  • Non-conductive reinforced vented coil former
  • Low damping rubber surround, symmetric suspension.
  • Long life silver lead wires
  • Strong vented steel chassis.

Basic parameters:

Resonant frequency (fs) 31.5 Hz Nominal impedance (Zn) 4 Ω
Mechanical  Q factor (Qms) 7.9
DC resistance (Re) 3.5 Ω
Electrical Q factor (Qes) 0.34
Max power handling 80 W
Total Q factor (Qts) 0.33
Sensitivity (2.83V/1m)
Equivalent volume (Vas) 47.8L Chassis
253 x 153mm

Here's the full datasheet:

.pdf link