How do I troubleshoot common issues with a stereo power amplifier?

Quick answer: To troubleshoot a stereo power amplifier, start with the simplest checks: power, source selection, pre-amplifier output, speaker wiring, input cables and ventilation. Stop using the amplifier if you smell burning, see smoke, repeatedly blow fuses or hear severe distortion.

No sound from either speaker

Confirm that the amplifier powers on, the pre-amplifier or processor is not muted and the correct input is selected. Then check RCA or XLR cables between the source/pre-amplifier and the power amplifier.

If you are using an AV receiver as a processor, make sure it has pre-outs and that the correct channels are assigned. Compare receiver options in AV receivers and amplifiers if your current unit cannot feed a separate amplifier.

Sound from one channel only

Swap left and right input cables. If the issue moves, the problem is upstream. If it stays on the same amplifier channel, check speaker cable, binding posts and the speaker itself. Always power down before moving speaker wires.

A stereo amplifier such as the Anthem STR Stereo Power Amplifier needs clean signal and secure speaker connections to perform correctly.

Hum, buzz or overheating

Hum can come from cable routing, ground loops, poor interconnects or connected source equipment. Keep signal cables away from power cables where possible. Overheating usually points to poor ventilation, low speaker impedance, high listening levels or blocked vents.

Basic troubleshooting order

• Power off the system before changing speaker wiring.
• Check source, volume and mute status.
• Inspect RCA or XLR input cables.
• Inspect speaker cables and binding posts.
• Test one source and one pair of speakers at a time.
• Allow enough ventilation above and around the amplifier.

Where to start on VisionSounds

Start with the Power Amplifiers collection, then compare matching speakers in floorstanding speakers, bookshelf and surround speakers and subwoofers.

If you are still deciding between a receiver and separates, compare AV receivers and amplifiers with home cinema products before choosing the final system path.

FAQ

Why does my amplifier hum?

Common causes include ground loops, cable routing, source equipment noise and faulty interconnects.

Why does my amplifier shut down?

It may be overheating, driving a difficult speaker load, shorting at the speaker terminals or entering protection mode.

When should I stop troubleshooting?

Stop immediately if there is burning smell, smoke, repeated fuse failure or severe distortion. Use qualified service help for electrical faults.