Belfast 820 - 8 Inch Guitar Speaker, 20 Watt, 4 Ohm

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The Belfast 820 provides players and listeners with a well-tailored and satisfyingly clear response. This model gives your tone a defined contour⁠—open and present lows, soft mids, and glassy/articulate highs—that will make your lead and solo lines soar.

Upgrade your 8-inch guitar speaker cabinet with this high-sensitivity driver, combining a powerful ferrite magnet motor, a 1-inch copper voice coil, a paper composite cone, and a pair of dual terminals for easy connectivity and installation, with a sturdy steel basket to hold it all in place.

  • British tone guitar speaker
  • 8 inch (203 mm) steel basket diameter
  • 20 watts, 4 ohm, 97 dB SPL
  • 1-inch copper voice coil, Kraft paper former
  • 10 oz ferrite magnet
  • Paper composite cone

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ToneSpeak guitar speakers result from years and years of deep-dive for the perfect tone. Decades of testing, field experience, and conversations with elite tone-chasers have all been poured into these fine products. When you play ToneSpeak, you play the best.

More Information
Brand Name ToneSpeak
Size, Nominal (inch & mm) 8" (203 mm)
Shape of Speaker Round
Speaker Type Guitar Speaker
Application Musical Instruments
Environment Indoor
RoHS Compliant Yes
Nominal Impedance (Z) (Ω) 4
Rated Power IEC268-5 (W) 20 Watts
Rated Impedance (Ω) 4
Continuous Power (W) 20
Program Power (W) 40
Frequency Range (Hz) 88 - 11,000
Sensitivity (dB SPL) ¹ 97
Resonant Frequency (Fs) (Hz) +/- 15% 155
DC Resistance (Re) (Ω) 3.4
Voice Coil Inductance (Le) (mH) 0.12
Mechanical Q Factor (Qms) 15.49
Electrical Q Factor (Qes) 1.77
Total Q Factor (Qts) 1.59
Mechanical Resistance (Rms) (kg/s) 0.58
Compliance Equivalent Volume (Vas) (L) 8.31
Suspension Compliance (Cms) (mm/N) 0.11
Surface Area of Diaphragm (Sd) (cm²) 226.98
Moving Mass (Mms) (gm) 9.22
Magnetic Gap Height (mm) 6.0
Coil Winding Height (mm) 6.35
Motor Force Factor (BL) (T•M) 4.17
Efficiency (η₀) (%) 1.69
Efficiency Bandwidth Product (EBP) (Fs/Qes) 87.88
Basket Type Stamped steel with black powder coating
Terminal Size (mm) 5.2 x 0.5
Voice Coil Diameter (mm) 25.4
Voice Coil Wire Material copper
Voice Coil Former Material Kraft paper
Voice Coil Winding Style Single Layer
Magnet Material Ferrite
Magnet Weight (g) 283.5
Cone Body Material Paper composite
Dust Cap Material Paper
Spider Material Cotton
Net Weight (kg) 1.02
Technical Notes

¹ Sensitivity is measured with 2.83 volt input, measured on-axis at 1 meter distance