Horizontal 1/3 Octave Polars
Architectural Specifications:
The loudspeaker shall be of in-ceiling design, consisting of a 114 mm (4.5 in) low frequency transducer, a 12 mm (0.5 in) tweeter, and fre- quency dividing network installed in an integral ported enclosure. The low frequency voice coil shall be 24 mm (1 in) in diameter and the cone shall be of lightweight injection molded graphite.
Performance specification of a typical production unit shall be as follows: Measured sensitivity (SPL at 1m [3.3 ft] with 2.83V input, averaged from 100 Hz to 10 kHz) shall be at least 86 dB-SPL. Usable frequency response shall extend from 85 Hz to 25 kHz (10 dB below rated sensi- tivity) with no external equalization. Rated power for 8 ohm unit shall be at least 15 watts continuous pink noise power, defined as conform- ing to international standard IEC 268-5 (shaped pink noise with peak-to-average ratio of 6 dB) for a period of 100 continuous hours.
The speaker shall have a nominal conical polar coverage pattern of 150 degrees (at -6 dB point), averaged 500 Hz to 10 kHz, and shall hold the same consistent polar coverage pattern when averaged in the intelligibility frequency band from 1 kHz to 4 kHz.
The backcan shall be constructed of formed steel and the baffle of UL94V-O fire rated medium impact polystyrene. An agency-rated enclosed-terminal wiring block shall be provided on the side of the backcan to allow positive screw-down connection of wiring.
The system shall include a support backing plate to reinforce the ceiling material and tile support rails for use on either 2 x 4 ft or 600 x 1200 mm suspended ceiling tiles, and which can be installed from beneath the ceiling tile.
Overall front face diameter shall not exceed 195 mm (7.7 in) and overall depth from the bottom of the ceiling shall not exceed 105 mm (4.1 in).
Control 24C Micro: Nominal impedance shall be 8 ohms. The loudspeaker shall weight no more than 1.6 kg (3.6 lb).
Control 24CT Micro: The loudspeaker shall be equipped with transformer for use in either 70.7V or 100V distributed-line speaker systems, with taps selectable by connecting the input wire to the selected enclosed wiring block terminal. Taps shall be nominally 8W @ 70V, 4W @ 70V (8W @ 100V), 2W @ 70V (4W @ 100V), 1W @ 70V (2W @ 100V) and 0.5W @ 70V (1W @ 100V). The loudspeaker shall weigh no more than 2.0 kg (4.4 lb).
The loudspeaker shall be the JBL Model Control 24C Micro (Control 24CT Micro).
