JBL GT5-12

Autohifi subwoofer

Manufacturer parameters
  • Diameter: 12" (30cm)
  • Power (W): 275/1100
  • Impedance (Ohm): 4
  • Sensitivity (db/1W): 87
  • Qts: 0,58
  • Price: 55
  • Diaphragm: polypropylene
  • Basket: sheet steel
  • Magnet:
Measured parameters
  • Fs = 30.03 Hz
  • Re = 3.50 ohms
  • Le = 3007.02 uH
  • Qt = 0.70
  • Qes = 0.78
  • Qms = 6.59
  • Mms = 256.16 grams
  • Cms = 0.000110 m/N
  • Vas = 34.22 liters
  • Sd= 471.44 cm^2
  • Bl = 14.684951 Tm
  • ETA = 0.11 %
  • Lp(2.83V/1m) = 86.25 dB (Sensitivity cca. 83dB/1W)
  • EBP=39 Hz (sealed)
These are the parameters of a brand-new driver, they may be a bit different after a burn-in.


SQ - Sealed 30l
SPL - Bassreflex 40l @ 52Hz (port area at least 110cm2)

Popular woofer made by JBL. I just don't get why, thanks to its heavy cone it has incredibly low sensitivity. Qts 0.7 is way too high, if you want to use it for SQ, you will need sealed enclosure, in bass-reflex it's only suitable for SPL and nothing else. The only pros are relatively good mechanical quality and relatively low price. However there are many better woofers in the same or lower price.