SB-5218 and SB-7218 are specially designed cinema subwoofers, featuring dual 500 and 700 watt, respectively, 18” (460mm) low-frequency transducers mounted in ported enclosures. They use B6 alignment with frequency range extending to below 25 hertz.
The SB-5218 and SB-7218 are cinema subwoofers with dual 18-inch low-frequency transducers in ported enclosures tuned to 25 Hz using a B6 alignment. They are intended for use with the B6 boost filter option provided by QSC SF-1 or SF-3 Subwoofer Filter modules or the QSC Digital Cinema Monitor.
The manual describes normal, parallel, and individual transducer connections, lists electrical and mechanical specifications for both models, and includes warranty and contact information for QSC Audio Products.
| Transducer power rating (SB-5218 / SB-7218) | 500 watts / 700 watts |
|---|---|
| Frequency range (SB-5218) | 24 - 100 Hz (±3 dB) |
| Frequency range (SB-7218) | 22 - 100 Hertz (±3 dB) |
| Usable range (SB-5218) | 19 - 250 Hz (-10 dB) |
| Usable range (SB-7218) | 19 - 250 Hertz (-10 dB) |
| Maximum output (SB-5218) | 135 dB SPL calculated peak |
| Maximum output (SB-7218) | 137 dB SPL calculated peak |
| Maximum continuous output (SB-5218) | 129 dBA SPL |
| Maximum continuous output (SB-7218) | 130.5 dBA SPL |
| Impedance (SB-5218) | 4 ohms nominal (3.2 @ 25 Hz, 62 @ 50 Hz) |
| Impedance (SB-7218) | 4 ohms nominal (3.2 @ 27 Hz, 28 @ 48 Hz) |
| Maximum input power, 100 hours (SB-5218) | 800 watts rms |
| Maximum input power, 100 hours (SB-7218) | 1200 watts rms |
| Maximum input power, 2 hours (SB-5218) | 1000 watts rms |
| Maximum input power, 2 hours (SB-7218) | 1500 watts rms |
| Recommended amplifier power (SB-5218) | 1600 watts rms maximum |
| Recommended amplifier power (SB-7218) | 2 600 watts rms maximum |
| Sensitivity, half space (SB-5218) | 99.5 dB |
| Sensitivity, half space (SB-7218) | 101.0 dB |
| Sensitivity, full space (SB-5218) | 93.5 dB |
| Sensitivity, full space (SB-7218) | 95.0 dB |
| Weight (SB-5218) | 225 lbs shipping, 205 lbs net (102/93 kg) |
| Weight (SB-7218) | 230 lbs shipping, 210 lbs net (104/95 kg) |
| Nominal coverage (both models) | Omnidirectional (80 Hz) |
| Recommended processing | LF boost: 25 Hz, Q=2.0, +6 dB |
| Connectors | Barrier strip screw terminals; up to #10 AWG stranded wire; four terminals |
| Transducers | Two 18-inch high-efficiency subwoofer transducers with vented 4-inch voice coils |
| Enclosure | B6 alignment, vented, tuned to 25 Hz, MDF, heavily braced |
| Size | 30 x 48 x 24 in (762 x 1220 x 610 mm) |
Use the B6 boost filter option provided by the QSC SF-1 or SF-3 Subwoofer Filter modules or the QSC Digital Cinema Monitor.
No. The enclosure is not designed to be suspended, flown, or rigged.
They accept up to #10 AWG stranded loudspeaker wiring.
QSC provides a 3-year limited warranty from date of sale (USA only).