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TROUBLESHOOTING
NO POWER, NO LIGHTS, NO FAN
Confirm that the AC cord is fully seated and connected to a live outlet. Check the AC source by trying another device such as a lamp. Check the BREAKER on the back of the amplifier by pushing in the button. If the breaker trips off quickly, the amplifier needs servicing.
AMPLIFIER LOSES VOLUME
If the amplifier is worked too hard, GuardRail™ will
reduce volume to prevent thermal muting. The fan should be running at full speed. Reduce input signal somewhat and the amp should return to normal gain within
EN serviced.
CHANNEL 1 PRODUCES DEEP BASS ONLY.
Check the position of the CROSSOVER switch on the rear panel. Set on FULL RANGE for normal, independent use of each channel.
CHANNEL 2 INPUT SEEMS DEAD.
Check the position of the CROSSOVER switch on the rear panel. Set on FULL RANGE for normal, independent use of each channel.
AMPLIFIER SOUNDS DISTORTED.
If the red CLIP LED is flashing, the amplifier is being played beyond its normal rated power. GuardRail™ circuitry will reduce volume somewhat to prevent severe overdrive, but if the input signal is further increased, the limiter can be overridden, with increased distortion.
If the speakers or speaker cables are shorted or defective, the amplifier may distort at
If too many speakers are connected to each channel (impedance below 4 ohms), the amp will overload more easily and will probably run hot.
If the sound is distorted or garbled without flashing the red CLIP LED, the distortion is not occurring inside the amplifier. Either the speaker is bad or the input signal is distorted.
• Confirm that the speaker is OK by trying a different unit.
• Input overload can occur if the amplifier Gain controls are set too low, and the input source is overdriven to compensate Reduce the source volume until the distortion clears up, and increase amp Gain to reach the desired level. It is generally desireable to keep the amp gains at or near their full, clockwise, position.
• Check all input connections. Do not plug two different sources into the same channel. Use a mixer to blend sources.
NO SOUND, WITH BLUE LED ONLY, NO GREEN OR RED LED
Confirm that the Gain controls are turned up. Confirm that the input cables are correctly installed at both ends. If using
NO SOUND, BUT THE GREEN LED IS RESPONDING The green LED indicates the amp is producing a signal, so sound should be heard if the speaker is connected. Check the speaker connections at both ends, and try a different speaker.
NO SOUND, RED LED ON
The amp mutes briefly when turned on and off to prevent thumps. If the amp overheats severely, it will mute until it cools off. The fan will be running at full speed, and sound should resume in less than a minute. If the amp feels hot and the fan is not running, it needs to be serviced.
BACKGROUND HUM
Balanced XLR or TRS cables are better for long runs. Hum can be a problem when connecting to
Hum can also occur earlier in the signal chain, depending on the types of connections. It often helps to plug everything into the same AC strip, if the total power consumption is not excessive.
As a last resort, mild hum can sometimes be reduced by lowering the amp gain, and increasing the source gain to compensate, but you must ensure that the source can deliver the extra volume without overload distortion. If this does not reduce hum, it is coming from the source.
AMPLIFIER NEEDS SERVICING
The following conditions indicate possible unsafe conditions that require service before using. If observed, unplug the AC cord from the wall and when safe, remove the amp for servicing.
• If the amplifier emits smoke or burning smells
• If the case is severely dented or deformed
• If the amplifier is soaked with any fluid
• If internal parts sound loose
• If the AC breaker trips when power is applied
• If the amplifier is dropped, carefully inspect for damage or loose parts before attempting to use.
