Architect & Engineer’s Specifications

AcousticDesign Series
AD-S402T

The professional surface mount loudspeaker system shall be a vertical column design utilizing full-range drivers. The transducers shall be four 2.75-inch (70 mm) drivers with weather-resistant paper cones. The loudspeaker system shall be capable of operation in direct low-impedance mode or over a 70/100V distributed audio line via a built-in low-saturation transformer.

The loudspeaker system shall meet the following performance criteria: effective frequency range of 110 Hz to 20 kHz (free-field, -10 dB from on-axis sensitivity); broad-band sensitivity of 85 dB SPL (on-axis, free-field sensitivity, 2.83 V in, measured at 1 m); maximum rated SPL (calculated) of 111 dB peak; rated power capacity of 31 V rms or 60 W (two-hours, IEC60268-1 noise); recommended amplifier power of 120 W; nominal impedance of 16 ohms. The loudspeaker system's nominal coverage angle (-6 dB) at 1 kHz shall be 80 degrees vertical and 180 degrees horizontal. The loudspeaker system shall include an internal compensation network that reduces side lobes in the acoustic radiation pattern.

The loudspeaker system connectors shall be mounted on a sealed, recessed input panel, with a 4-terminal Euroblock connector having parallel input and output terminals. The loudspeaker system’s transformer tap selector switch shall be a five-position rotary type and shall also reside on the input panel. The tap selections shall be 16 ohm (bypass); 30 W (70V) and 60 W (100V); 15 W (70V) or 30 W (100V); and 7.5 W (70V) or 15 W (100V).

A weather-tight cover for the input panel shall be provided for optional protection against precipitation and other moisture. The loudspeaker enclosure, which shall meet IEC60529 IP-54 specifications for dust and splash resistance, shall be constructed of aluminum and finished in either of two RAL colors: black (9011) or white (9010). The front of the enclosure shall be protected by a powder-coated aluminum grille. The manufacturer’s logo on the front grille shall be removable without leaving a blemish.

The loudspeaker system shall include a surface mounting bracket that allows the enclosure 0 to 20 degrees of downward tilt, in 5-degree increments, and up to ±55 degrees of horizontal panning. On its rear panel the enclosure shall offer three different mounting positions for the bracket and shall also have three M6 threaded holes for shoulder eye bolts to be used for attaching safety tethers or for horizontally suspending the loudspeaker.

The enclosure shall be 12.9 in (327.5 mm) high, 5.2 in (131 mm) wide, and 5.0 in (126 mm) deep. With the mounting bracket installed, the front of the grille shall stand 7.1 in (179 mm) from the mounting surface when set for zero tilt. The loudspeaker system shall have a net weight of 7.5 lb (3.4 kg).

The surface-mount column loudspeaker system shall be the QSC AD-S402T.