User manual ELECTRO-VOICE APX-200 DATASHEET

[. . . ] Additionally, two port plugs are included for the customer to install when increased weather resistance is needed. Through extensive use of computeraided design and modeling, Electro-Voice engineers have developed a state-of-the-art professional loudspeaker system for permanent installations where weather resistance is needed. The high-frequency section of the Sx500PI+ utilizes a molded-in 75° x 60° constant-directivity horn which is aimed downward by 10°. This unique pattern contributes to high intelligibility and aims the speaker's output where it is most useful. [. . . ] Figures 1a and 1b have been averaged and corrected for 1 watt at 1 meter. Port Plugs The two ports, on either side of the high-frequency horn, may be "sealed" in order to add further weather protection to the system. These optional foam port plugs are included with the system for use in situations where increased weather resistance is needed. This will help prevent any moisture from wicking through the foam-backed grille and accumulating inside the enclosure under extreme weather condidtions. The optional port plugs and instructions are supplied with each system. It should be noted, however, that once the port plugs are installed, 2 the frequency response will change to that shown in Figure 1b. Connections and Biamping The Sx500PI+ is equipped with two parallel Neutrik Speakon® NL4MP connectors. In the full-range mode, as supplied by the factory, pins 1+ and 1­ are the inputs to the system. Another system can be connected in parallel by using the other connector. Care must be taken not to abuse the amplifier by connecting impedances which are too low. The user may put the system in biamp mode by removing the input panel and moving a connector from the full-range mode to biamp mode, as noted on the crossover. Amplifier Power Recommendations As noted in the Power-Handling Capacity section above, the Sx500PI+ has a random-noise power capacity of 400-watts long term (1, 600- watts peak) per ANSI/EIA RS-426-A 1980. The following guidelines will help relate this to an appropriate power amplifier output rating. Sx500PI+ 400-Watt Two-Way Weather-Resistant Speaker System Sx500PI+ 400-Watt T wo-Way Weather-Resistant Speaker System 1. To use the Sx500PI+ to full capacity, skilled experts in sound-system installation and operation will obtain the best results if the power amplifier is 2. 0 to 4. 0 times the longterm average noise- power rating of the speaker system. For the Sx500PI+, this is 800 to 1, 600 watts. The caution cannot be made strongly enough, however, that this arrangement is only for experts or those who can discipline themselves against "pushing" the system for ever-higher sound levels and who can avoid "accidents" such as catastrophic feedback or dropped microphones. A more conservative, "normal" amplifier size, which will produce audible results nearly equal to those of the "expert" recommendation, is 1. 0 to 1. 4 times the longterm average noise-power rating of the speaker. For the Sx500PI+, this is 400 to 640 watts. To be very conservative, one can use an amplifier rated at 0. 5 to 0. 7 times the longterm average noise-power rating of the speaker. For the Sx500PI+, this is 200 to 280 watts. Two ("Power Handling Capacity") for more background on these recommendations. Service In the unlikely event the Sx500PI+ requires service, the woofer can be removed from the front. [. . . ] Before the enclosure is suspended, these inserts are used to attach plates that hold the two halves of the enclosure together in addition to providing a way to suspend the enclosure. The suspension kits that are available for the Sx500PI+ are listed below. Please refer to individual suspension-kit engineering data sheets for full details and safety information. The first approach is to suspend individual Sx500PI+ enclosures. [. . . ]