Almighty Subwoofers
By Stig Erik Tangen
01 Jan 1997
JBL 2226 G/H/J - 380 mm Low Frequency Transducer
Key features:
600W AES continous pink noise power capacity
100 mm edgewound aluminium ribbon voice coil
30-2.5 kHz response
97 dB sensitivity, 1W, 1m
SFG (Symmetrical Field Geometry) magnet structure with Vented Gap Cooling (tm) technology
Computer-optimized magnet design for reduced weight and maximum flux density
Glass fiber / paper composite cone
Die-cast aluminium frame
Ideal for tour sound and fixed installations, as well as critical high level monitoring
Specs:
Nominal diameter 380 mm
Rated Impedance 4/8/16 ohm (G/H/J)
Power Capacity 600W AES continous pink noise (AES standard, 50-500 Hz)
Sensitivity 97 dB SPL / 1W / 1m (2V @ 4 ohms (G), 2.183V @ 8 ohms (H), 4V @ 16 ohms (J))
Frequency Range 30-2.5 kHz (-10 dB)
Power Compression 0.7 dB at -10 dB power (60W) 2.5 dB at -3 dB power (300W) 4.0 dB at rated power (600W) Power compression is the sensitivity loss at the specified power, measured from 50-500 Hz, after a 5 minute AES standard pink noise preconditioning test at the specified power
Distortion 2nd harmonic <1% @ 60W, 50-500 Hz 3rd harmonic <1% @ 60W, 50-500 Hz
Highest Recommended Crossover 1200 Hz
Recommended Enclosure Volume 85-285 l
Effective Piston Diameter 335 mm
Maximum Excursion Before Damage 40 mm (p-p)
Minimum Impedance 3.0 ohms ±10% @ 25 ºC (G) 6.0 ohms ±10% @ 25 ºC (H) 12.0 ohms ±10% @ 25 ºC (J)
Voice Coil Diameter 100 mm
Voice Coil Material Edgewound aluminium ribbon
Voice Coil Winding Depth 19.05 mm
Magnetic Gap Depth 8.1 mm
Magnetic Assembly Weight 6.8 kg
B*l factor 13.5 N/A (G) 19.2 N/A (H) 27.1 N/A (J)
Effective Moving Mass 0.098 kg
T/S parameters (after break-in)
Fs 40 Hz
Re 2.5 ohms (G) 5.0 ohms (H) 10.0 ohms (J)
Qts 0.31
Qms 5.00
Qes 0.33
Vas 175 l
Sd 880 cm²
Xmax 7.6 mm
Vd 689 cm³
Le 0.92 mH (G) 1.75 mH (H) 3.5 mH (J)
no 3.3%
Pe 600 W
Frequency Response and Impedance Curves
Measured in 280 l closed box, hemispherical free-field, on axis. Dotted line 45 degrees off axis. Dashed curve 140 l / 40 Hz vented box. Impedance measured in free air. (Click the image for a larger view.)
Distortion curves
Distortion levels raised 20 dB. Measured at 60 W, 1 meter in 280 liter closed box. (Click the image for a larger view.)
JBL's distortion measurement show signs of cone breakup modes above 150 Hz causing an increase in distortion. Of this reason high performance is only to be expected at low frequencies. I recommend a maximum crossover at 150 Hz. In less critical applications 300 Hz may be an acceptable crossover frequency.
Also note that the distortion is measured at a very high input power, 60W. Distortion measurements on "hi-fi" drivers are usually carried out at only 2-5 W input.
The JBL 2226 is extremely noise-free, meaning there are virtually no rattling or "breathing" at large cone excursions, an otherwise very common phenomenon.
All JBL drivers share this same pecularity; the black terminal is positive and the red negative, or as JBL puts it: "Positive voltage on BLACK terminal gives forward diaphragm motion". The terminals look cheap, but they work surprisingly well.
Don't the JBL 2226 have flaws that should be corrected by modification? Well, I have to admit that any limitations are hard to find!
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