User manual ELECTRO-VOICE AR400 DATASHEET

[. . . ] The high-frequency section of the Sx300PI utilizes a molded-in, 65° x 65° constant-directivity horn. This unique pattern contributes to high intelligibility. Vocals sound natural, yet "cut through" in reverberant, noisy rooms. In addition, the coverage pattern is unusually uniform over its range of operation. [. . . ] Directivity A unique feature of the Sx300PI is the constant-directivity dispersion provided by the 65° x 65° horn. The polar response of the system at selected one-third-octave band2 Sx300PI and Sx300PIX 300-Watt Two-Way Weather-Resistant Speaker Systems widths is shown in Figure 2. These polar responses were measured in an anechoic environment at 10 feet using one-third-octave pink-noise inputs. The frequencies selected are fully representative of the polar response of the system. Beamwidth of the system utilizing the complete one-third-octave polar data is shown in Figure 4. Rq and directivity index (Di) are plotted in Figure 5. Suspending Sx300PI Enclosures WARNING: Suspending any object is potentially dangerous and should only be attempted by individuals who have a thorough knowledge of the techniques and regulations of rigging objects overhead. Electro-Voice strongly recommends that the Sx300PI be suspended taking into account all current national, federal, state and local regulations. It is the responsibility of the installer to ensure the Sx300PI is safely installed in accordance with all such regulations. If the Sx300PI is suspended, Electro-Voice strongly recommends that the system be inspected at least once a year. If any sign of weakness or damage is detected, remedial action should be taken immediately. Second, our signal contains more energy at extremely high and low frequencies than typical actual program, adding an extra measure of reliability. Third, the test signal includes not only the overall "long term average" or "continuous" level-- which our ears interpret as loudness--but also short-duration peaks which are many times higher than the average, just like actual program. The long-term average level stresses the speaker thermally (heat). The instantaneous peaks test mechanical reliability (cone and diaphragm excursion). Note that the sine-wave test signals sometimes used have a much less demanding peak value relative to their average level. In actual use, long-term average levels exist from several seconds on up, but we apply the long-term average for several hours, adding another extra measure of reliability. Specifically, the Sx300PI is designed to withstand the power test described in the ANSI/EIA RS-426-A 1980. The EIA test spectrum is applied for eight hours. To obtain the spectrum, the output of a white-noise generator (white noise is a particular type Sx300PI and Sx300PIX 300-Watt T wo-Way Weather-Resistant Speaker Systems of random noise with equal energy per bandwidth in Hz) is fed to a shaping filter with 6-dB-per-octave slopes below 40 Hz and above 318 Hz. When measured with the usual constant-percentage bandwidth analyzer (one-third-octave), this shaping filter produces a spectrum whose 3-dB-down points are at 100 Hz and 1, 200 Hz with a 3-dB-per-octave slope above 1, 200 Hz. This shaped signal is sent to the power amplifier with the continuous power set at 300 watts into the 7. 1-ohm EIA equivalent impedance (46. 2 volts true rms). [. . . ] Sx300PI Connections The Sx300PI is equipped with two Neutrik Speakon ® NL4MP connectors. In continued high-power applications, Electro-Voice recommends the use of the Speakon connector. The Speakon NL4MP will mate to a NL4FC Speakon connector, which is a 4-pin connector. Figure 7 shows typical wiring configurations using banana plugs. [. . . ]