Mackie SA1521 Owner's Manual - Page 7

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: Troubleshooting No power • Our favorite question: Is it plugged in? Make sure the AC outlet is live (check with a tester or lamp). • Our next favorite question: Is the POWER switch on? If not, try turning it on. • Is the POWER LED on the rear panel glowing green? If not, make sure the AC outlet is live. If so, refer to "No sound" below. • The internal AC line fuse may be blown. This is not a user serviceable part. If you suspect the AC line fuse is blown, please see the REPAIR section next. No sound • Is the input LEVEL control for the input source turned all the way down? Verify that all the volume controls in the system are properly adjusted. • Is the signal source working (and making union scale)? Make sure the connecting cables are in good repair and securely connected at both ends. Make sure the output volume (gain) control on the mixing console is turned up sufficiently to drive the inputs of the speaker. • Make sure the mixer does not have a Mute on or a Processor loop engaged. If you find something like this, make sure the volume/gain is turned down before disengaging the offending switch. • 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. Verify that all level controls are set properly. • Is the input connector plugged completely into the jack? Be sure all connections are secure. It's a good idea to periodically clean all electrical connections with a non-lubricating electrical contact cleaner. 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. • Is there a light dimmer or other SCRbased device on the same AC circuit as the SA1521? Use an AC line filter or plug the SA1521 into a different AC circuit. Hum • Try disconnecting the cable connected to the MAIN INPUT jack. If the noise disappears, it could be a "ground loop," rather than a problem with the SA1521. Try some of the following troubleshooting ideas: • Use balanced connections throughout your system for the best noise rejection. • Whenever possible, plug all the audio equipment's linecords into outlets which share a common ground. The distance between the outlets and the common ground should be as short as possible. 7