Finding the source of noise in an audio system is no easy task. Any audio equipment or cabling can generate noise on its own, including the power amplifier. Noise can come in many forms including humming, buzzing, static, crackling, or ringing. Use the procedures below to determine if the noise is being produced by a QSC amplifier or powered loudspeaker. If the noise is found to be self-generated by the QSC product, then it will need to be serviced. Please read about your service and support options.
The most basic setup of a QSC amplifier includes 3 components: a line-level source, power amplifier, and passive loudspeaker.
A powered loudspeaker has a built-in amplifier which simplifies the audio system. The most basic setup includes 2 components: a line-level source and powered loudspeaker.
In order to determine if the QSC product is the source of the noise, we must isolate it from the audio system. Please follow the instructions below for your specific application.
If no noise is heard, then there is a strong chance that a device or cable upstream from the amplifier is the source of the noise. Reconnect the input cables to the amplifier. To isolate the noisy source, disconnect cables one-by-one from the upstream audio equipment until the noise disappears. If the noisy source cannot be found using this method, try a completely different source and cables, preferably from a known well working audio system.
A very light static noise may be heard from the loudspeaker if you are listening less than 10 feet from the loudspeaker. This is perfectly normal. If the gain sensitivity or MIC switch is engaged on the powered loudspeaker, noise is likely to be heard from the loudspeaker due to the increased sensitivity.