User manual MACKIE SRM450

[. . . ] SRM450 ACTIVE SOUND REINFORCEMENT SPEAKER USER'S MANUAL CAUTION AVIS 8. Heat -- This Mackie product should be situated away from heat sources such as radiators, or other devices which produce heat. Power Sources -- This Mackie product should be connected to a power supply only of the type described in these operation instructions or as marked on this Mackie product. Power Cord Protection -- Power supply cords should be routed so that they are not likely to be walked upon or pinched by items placed upon or against them, paying particular attention to cords at plugs, convenience receptacles, and the point where they exit this Mackie product. [. . . ] It's better to place the active speakers on a sturdy table or tripod stands. · Position the active speakers so the highfrequency drivers are two to four feet above ear level for the audience (make allowances for a standing/dancing in the aisles audience). High frequencies are highly directional and tend to be absorbed much easier than lower frequencies. By providing direct line-ofsight from the active speakers to the audience, you increase the overall brightness and intelligibility of the sound system. · Highly reverberant rooms, like many gymnasiums and auditoriums, are a nightmare for sound system intelligibility. Multiple reflections off the hard walls, ceiling, and floor play havoc with the sound. Depending on the situation, you may be able to take some steps to minimize the reflections, such as putting carpeting on the floors, closing draperies to cover large glass windows, or hanging tapestries or other materials on the walls to absorb some of the sound. Making the sound system louder generally doesn't work because the reflections become louder, too. The best approach is to provide as much direct sound coverage to the audience as possible. The farther away you are from the speaker, the more prominent will be the reflected sound. Use more speakers strategically placed so they are closer to the back of the audience. If the distance between the front and back speakers is more than about 100 feet, you should use a delay processor to time-align the sound. (Since sound travels about 1 foot per millisecond, it takes about 1/10 of a second to travel 100 feet). RIGGING The SRM450 cabinets are fitted with ten rigging points as shown in the diagram below. M10 threaded eyebolts (M10 x 1. 5 mm x 20 mm) are available to fit these inserts (PA-A1 Eyebolts). WARNING: Never attempt to suspend the SRM450 active speakers by their handles. Consult a professional rigger or structural engineer prior to suspending loudspeakers from a structure not intended for that use. Always know the working load limit of the structure supporting the loudspeaker array. Always make sure that the rigging hardware minimum rating is at least five times the actual load. Back Both Sides SRM450 Pole Mount Rigging Points Top Bottom If you are hanging them in an inaccessable place, such as over a lion's cage, make sure that you first complete the sound check and set the SRM450 LEVEL correctly. Also set the TIMED TURNOFF switch if you want the SRM450 to turn on when there is a signal present. 11 THERMAL CONSIDERATIONS The amplifiers inside the SRM450 are convection cooled by a large heatsink. For efficient cooling, it is important to allow at least six inches of free space behind the SRM450. If you use the SRM450 on its side for stage monitor applications, we highly recommended that you engage the rear panel LOW CUT switch. [. . . ] It is necessary to establish purchase date and thus determine whether or not your loudspeaker is still under warranty. If you can't find it, the Authorized Service Center may charge you for repairs even if your loudspeaker is still covered by the Five-Year Limited Warranty. If you bring your loudspeaker to an Authorized Service Center and they can't find anything wrong with it, you may be charged a service fee. If the Authorized Mackie Service Center is located in another city, pack the loudspeaker in its original shipping carton. [. . . ]