The [short throw] speaker shall be a slim profile two-way, direct-radiating, clothoid curved line array design, TOA Electronics model SR-S4S.   The low-frequency section shall consist of eight direct-radiating 10 cm cone-type drivers arranged in a vertical line and housed in a tuned and ported enclosure featuring a clothoid (‘J’) curve-shaped profile.  The high frequency section shall consist of 24 direct-radiating 25 mm balanced-dome tweeters arranged in a vertical line.  The tweeters shall be mounted centrally in front of the low frequency drivers, sharing the same horizontal axis and the same clothoid curve-shaped profile. 

The integral frequency dividing network shall include both low pass and high pass filter sections and shall be optimized for smooth on-and off-axis frequency response.  The crossover frequency shall be 3,500 Hz.  Biamp operation shall be possible by changing the internal connections of the input connector panel.  The speaker input connectors shall include two screw terminal connections and two Neutrik NL4 type sockets, wired in parallel for pass-through to additional speakers.  In biamp mode, the NL4 sockets shall allow for discreet connection of both the LF and HF sections via a single NL4 plug using 4-conductor cable.  In biamp mode, pass-through of the biamp signal shall be possible by connection to the parallel-wired socket.

The speaker’s horizontal and vertical coverage shall be consistent with that of a clothoid curved line array design. The horizontal coverage shall be 90 degrees nominal above 2,000Hz.  The vertical coverage shall be 10 degrees nominal. Extending the coverage area shall be possible by stacking one or two straight line array systems, model SR-S4L, above a single clothoid curved line array system, model SR-S4S.  The consistency of coverage shall not be degraded when multiple units are stacked.

The speaker shall meet the following performance criteria.  Power handling (full range): 200 watts continuous pink noise (24 continuous hours, 50 Hz to 20 kHz), 360 watts continuous program. Power handling (biamp mode) Low Frequency input: 80 watts continuous pink noise (24 continuous hours, 50 Hz to 4 kHz), 150 watts continuous program; High Frequency input: 80 watts continuous pink noise (24 continuous hours, 4 kHz to 20 kHz), 150 watts continuous program.  Frequency response (10 dB below rated pressure sensitivity, with recommended equalization/without recommended equalization):  70 Hz to 20 kHz / 80 Hz to 20 kHz.  Pressure sensitivity (1 watt at 1 m, 230 to 2,500 Hz): 94 dB.  Impedance: 8 ohms nominal. When the optional line matching transformer model MT-S0601 is installed, the available power taps for 70.7 volt line applications shall be 7.5, 15, 30, and 60 watts (670, 330, 170, and 83 ohms respectively).

The speaker enclosure shall be made of medium density fiberboard and finished with white paint.  The speaker grille shall be made from a single punched steel plate and finished with white acrylic paint. The dimensions (W x H x D) shall be 6.3” x 35.24” x 10.04” (160 mm x 895 mm x 255 mm) and weight shall be 35.3 lbs. (16kg).  The speaker enclosure shall be equipped with threaded inserts for the attachment of optional accessory brackets.  Available accessory brackets for flying, and for wall, ceiling and stand mounting shall be made of steel.

The loudspeaker shall be TOA model SR-S4S.
The matching transformer shall be TOA model MT-S0601.
The extension plate shall be TOA model SR-EP4.
The flying bracket shall be TOA model SR-FB4.
The wall tilt bracket shall be TOA model SR-TB4.
The stand adapter shall be TOA model SR-SA4.
The protection pad shall be TOA model SR-PP4.