Read the SB-15121 application note: covers the target applications of the SB-15121, as well as advantages and comparisons to other cinema subwoofer designs.
Frequency Range 1
Maximum Output 2
4 ohms nominal
Maximum Input Power 3
Recommended Amplifier Power
3400 W continuous maximum / 1200 W continuous minimum
Sensitivity 2 V at 1 meter, half space
99 dB, 40 Hz–100 Hz
Omnidirectional (80 Hz)
One 21" (533 mm) high efficiency subwoofer transducer featuring a vented 6" (153 mm) copper voice coil on a fiberglass former. High excursion/low distortion design, with extremely high power handling and low thermal and port compression. Neodymium magnet to provide a very high force factor and linear excursion.
HPF at 20 Hz, minimum 12 dB/octave slope
Barrier strip screw terminals accept up to #10 AWG stranded wire. Four terminals; two inputs and two parrallel outputs.
Vented enclosure with symmetrical port design, tuned to 25 Hz, constructed of medium density fibre-board and heavily braced. Features vandal resistant woofer mounting bolts.
Dimensions (HWD) inches
48.8 × 30 × 24
Dimensions (HWD) mm
1238 x 762 x 610
231 lb (105 kg)
257 lb (114 kg)