User manual MACKIE SA1521

[. . . ] SA1521 2-WAY ACTIVE SPEAKER SYSTEM USER'S MANUAL CAUTION AVIS RISK OF ELECTRIC SHOCK DO NOT OPEN RISQUE DE CHOC ELECTRIQUE NE PAS OUVRIR CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK DO NOT REMOVE COVER (OR BACK) NO USER-SERVICEABLE PARTS INSIDE REFER SERVICING TO QUALIFIED PERSONNEL 9. 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. Object and Liquid Entry -- Care should be taken so that objects do not fall into and liquids are not spilled into this Mackie product. [. . . ] A suspected problem of "poor bass performance" is often caused by a weak AC supply to the amplifiers. CAUTION: Never remove the ground pin on the power cord of the SA1521 or any other component. This is very dangerous. THERMAL CONSIDERATIONS The SA1521 has two powerful built-in amplifiers capable of producing a combined 500 watts of power. As amplifiers produce heat, it is important to dissipate the heat as quickly as possible. This results in increased reliability and longevity for the amplifier. The amplifier module is mounted on a large heatsink, which is cooled by convection where cool air is drawn through it's fins, carrying the heat away. In order for this convection cooling to work efficiently, it is important to provide adequate airspace behind the loudspeaker. When you position the SA1521, we recommend leaving at least six inches of air space behind it. In the unlikely event of the amplifier overheating, a built-in thermal switch will activate, which mutes the signal and lights the THERMAL LED. When the amplifier has cooled down to a safe operating temperature, the thermal switch resets itself, and the SA1521 resumes normal operation. If the thermal switch activates frequently, try turning down the level control a notch or two on the mixing console (or the back of the SA1521) to avoid overheating the amplifier. If the temperature in the room is too high, it could cause the amplifier to overheat. In this case, you should try aiming a fan at the rear panel to move more air through the fins. AC POWER Be sure the SA1521 is plugged into an outlet that is able to supply the correct volt6 SERVICE INFORMATION Warranty Service If you think your loudspeaker has a problem, please do everything you can to confirm it before calling for service, including reading through the following Troubleshooting section. Doing so might save you from being deprived of your Mackie loudspeaker. Of all Mackie products returned for service (which is hardly any at all), many are coded "CND" -- Could Not Duplicate-- which usually means the problem lay somewhere else in the system. The following troubleshooting tips may sound obvious, but here are some things you can check: · Is the THERMAL indicator lit red on the rear panel?Make sure there is at least six inches of free space behind the SA1521. Poor bass performance · Check the polarity of the connections between the mixer and the loudspeakers. You may have your positive and negative connections reversed at one end of one cable, causing one loudspeaker to be out-of-phase. Poor sound · Is it loud and distorted?Make sure that you're not overdriving a stage in the signal chain. It's a good idea to periodically clean all electrical connections with a non-lubricating electrical contact cleaner. Troubleshooting No power · Our favorite question: Is it plugged in?If you suspect the AC line fuse is blown, please see the REPAIR section next. Noise · Make sure all connections to the active loudspeakers are good and sound. · Make sure none of the signal cables are routed near AC cables, power transformers, or other EMI-inducing devices. [. . . ] Make sure that you have a copy of your loudspeaker's sales receipt from the store where you bought the product. 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. [. . . ]