Appendix A: Service Information
Warranty Service
Details concerning Warranty Service are spelled out in the Warranty section on page 19.
If you think your amplifier has a problem, please do everything you can to confirm it before calling for service. Doing so might save you from the deprivation of your amplifier and the associated suffering.
These may sound obvious to you, but here are some things you can check. Read on.
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 red LED next to the POWER switch illuminated? If not, make sure the AC outlet is live. If so, refer to “No Sound” below.
•Has the BREAKER switch popped? Try pushing in the BREAKER switch. If it pops out again right away, refer to “Repair” on the next page.
•The AC fuse inside the amplifier is blown. This is not a
No Sound
•Are the channel Level controls turned up? Slowly turn them up and see if you hear anything.
•Is the signal source turned up? Make sure the signal level from the mixing console (or whatever device immediately precedes the amplifier) is high enough to produce sound in the amplifier. The SIG LEDs should be blinking to indicate that signal is present.
•If the speakers are wired for BRIDGE mode, make sure the AMP MODE switch is set to
BRIDGE.
•If the amplifier has gotten extremely hot, the thermal protection circuit may have activated. Allow the amplifier to cool down and normal operation should resume.
•Are there fuses in the speakers, or
•Make sure the speakers are working properly.
One side is way louder than the other
•Are both Level controls set to the same position?
•Check your source signal to make sure the left and right signals are balanced.
•Are the speaker impedances matched? Different speaker loads can cause different volume levels on each side.
•Try switching sides: Turn off the amp, swap the speaker cables at the amp, turn the amp back on. If the same side is still louder, the problem is with your speaker cabling. If the other side is louder now, the problem is with the mixer, the amp, or the
The stereo music sounds kind of sideways, and the bass frequencies diminish when standing center, but get louder as you approach one side
•Check the polarity of the speaker cable connections. You may have your positive and negative reversed at one end of one speaker cable.
As soon as the music gets loud, the amp shuts down
•Check the OL LEDs and make sure that they are not lighting continuously. If they are, turn down the signal source or the Level controls on the amp.
•Can the amp breathe? The amplifier draws its ventilation air in from the back. It needs plenty of fresh air to stay cool. Do not block the ventilation holes.
I hear thunder, even when the amplifier is turned off
•It’s going to rain. Get inside quickly. Bring the amplifier with you.
Poor sound
•Is it loud and distorted? Turn down the signal coming from the mixer or signal source.
•Is the input connector plugged completely into the jack? Check the speaker connections and verify that all connections are tight and that there are no stray strands of wire shorting across the speaker terminals.
•If possible, listen to the signal source with headphones plugged into the console. If it sounds bad there, the problem is not in the amplifier.
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