Sunfire TGA-7401-230, TGA-7201, TGA7401 Troubleshooting Guide, No sound from one or more speakers

APPENDIX

Troubleshooting Guide

The Sunfire Amplifier is expertly designed and built to provide years of trouble-free performance. Most prob- lems that occur can usually be solved by checking your setup or making sure that the audio and video com- ponents connected to your processor are on and fully operational.

The following information will help you deal with common setup problems you may experience during normal use of your unit. If the problems still persist, please contact your Sunfire Dealer for assistance.

No sound from one or more speakers

•Speaker cables may have come undone. Turn off your system and check the cables, and tighten the amplifier and speaker binding posts.

•Broken audio cable.

•The preamplifier volume level is low for the channels concerned.

Recheck the preamplifier calibra- tion procedure.

•A preamplifier Mute switch may be on, or an external processor loop or a tape monitor loop is engaged.

•Check that your preamplifier or source is running the correct sur- round sound mode. Maybe it is set for stereo when you were expect- ing 5.1 surround sound.

•Check in case any missing chan- nels have been turned off in a preamplifier setup menu. For example, the center amplifier channel will not receive a signal if the preamplifier has been set to

"Phantom."

•The Auto/on/off switch might be in the off position.

•One of the fuses for the current source outputs may have blown.

The amplifier shuts down often or the line fuse blows often

•Check that the positive and nega- tive speaker wires are not shorted together.

•Make sure that no speakers are shorted internally. If you have an ohm-meter, disconnect the speaker wires and measure the resistance between the speaker’s positive and negative terminals. If the read- ing is less than 2 ohms, the speak- ers may have an internal short. Measure all speakers and check their impedance specifications.

•If you have connected speakers in Parallel, the overall impedance may be too low. It is recommended that you rearrange the speakers in Series to increase the overall impedance, thus taking some of the load off the amplifier.

•Make sure that the amplifier has good ventilation and is not overheating. If the amplifier is in a closed rack, open up the rear panel or use a quiet fan for im- proved ventilation.

A hum is heard in your speakers

This problem is more than likely caused by a “ground loop” in your sys- tem, rather than a fault in the amplifier. Follow these steps to isolate the main cause of the hum; there may even be more than one.

•If your preamplifier has XLR bal- anced outputs, use them because they offer greater immunity to noise fields.

•Remember to unplug all compo- nents in your system, including the amplifier, before disconnecting or connecting any cables during troubleshooting.

•Try to have all of your equipment on the same electrical outlet or circuit. Group all the low power components (preamp, CD player,

DVD etc.) on a single outlet or power strip. This is provided that the overall current draw from your equipment does not exceed the rating of the outlet or breaker.

•Disconnect all cables which come from outside the room, and check if the hum goes away. This in- cludes such connections as cable TV, satellite TV, or roof top an- tennas. Make sure that they are disconnected where they first enter the room, so they are making no connection to the preamplifier or the TV, or any other component. If the hum is caused by the cable TV line, then you will need a “ground loop isolator.” This is an inexpen- sive device fitted in line with the coaxial cable feed. Contact your cable company or your Sunfire

Dealer for assistance.

•Disconnect all connections from the preamplifier to your TV, VCR or

DVD.

•As a test, disconnect any other component which has a grounded power cord.

NOTE: Never remove the ground pin from any power cords. This is very dan- gerous.

•If the hum persists, disconnect all the source components one at a time from the back of the preampli- fier, until you identify the problem.

•Ground loop isolators are available for audio lines and video. You can ask your Sunfire Dealer for assis- tance.

•Try moving the speaker cables away from any power cords. Try just one speaker, connecting it to each amplifier channel and see if one channel is bad.

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User's Manual