Architect and Engineer’s Specifications: 
AD-C.SUB Small Format Ceiling Subwoofer

The subwoofer enclosure shall contain a low-saturation, low-loss transformer so it can operate on 70- or 100-volt distributed lines, or as a direct low-impedance system when the transformer is bypassed. The transformer shall have multiple taps to allow selection of the desired power level on 70- or 100-volt lines. The subwoofer shall feature a 6.5-inch dynamic woofer driver with a weather-treated paper cone, and a rubber surround. The driver shall have dual 8-ohm voice coils connected in parallel to present a 4-ohm load when the subwoofer is switched to low impedance. A rotary switch on the face of the subwoofer baffle shall offer this selection of power levels, as well as a transformer bypass: 100, 50, 25, and 12.5 watts (70 volts); 100, 50, and 25 watts (100 volts). The switch shall be accessible under a removable magnetic snap-fit powder-coated perforated steel grille.
The subwoofer enclosure shall contain a passive crossover filter system, with the 150 Hz low-pass filter delivering content into the subwoofer driver and the 200 Hz high-pass filter delivering content for the satellite loudspeakers to output connectors on the enclosure.
The subwoofer shall have an effective frequency range of 45 Hz to 150 Hz and an on-axis free-air sensitivity of 86 dB SPL, measured at 1 m with an input signal of 2 V rms. It shall be capable of producing a peak maximum output of 106 dB SPL, measured at 1 m. The subwoofer’s continuous power rating, measured with an IEC60268-1 noise signal for two hours, shall be 100 watts (20 volts rms with transformer bypassed).
The subwoofer enclosure shall be a powder-coated steel can with a round baffle made of ABS plastic and shall carry UL1480 and UL2043 certification. The only parts of the enclosure that shall be visible below the ceiling are a plastic trim ring and the grille. The subwoofer shall be available with the trim ring and grille in either RAL 9010 white or RAL 9011 black.
The connectors on the subwoofer enclosure shall be three locking four-pole “Eurostyle” pluggable terminal blocks located in a recess on the top side of the can. The recess shall be protected by a removable conduit cover plate. The input terminal block shall offer two connection points, + and -, for the loudspeaker cabling and two more parallel loop-through connection points for connecting forward to another subwoofer unit, if necessary. A second four-pole terminal block shall provide high-pass + and - outputs for two satellite loudspeakers (SAT 1 and SAT 2), and a third shall provide high-pass + and - outputs for satellites SAT 3 and SAT 4, if necessary.
The subwoofer enclosure shall have a blind mounting system comprising four stepped, long-travel dog ears. Mounting hardware included with each subwoofer shall be a C-ring and tile rails, along with joining screws and a cut-out template. The enclosure shall be sized to fit a circular cutout with a diameter of 302 mm (11.89 inches). The outside diameter of the trim ring shall be 340 mm (13.39 inches), and the overall height of the subwoofer system shall be 254 mm (10.0 inches). There shall be an attachment ring on the can for a seismic safety tether. The subwoofer system shall weigh 8.70 kg (19.1 lb) net.
The subwoofer shall be the QSC AD-C.SUB.