Power amp rumbling noise

[LucienAndTheBeats]

Hi there.

I have just bought a Stage Line STA-100 pro power amplifier to use with some eltax speakers.

The problem is when I connect both speaker via speaker cables to the back of the amp, the amp start to make a low rumbling noise. Also when i adjust the left and right volumes on the amp it makes the speakers crackle a bit.

Anyone know what this could be?

Thanks

 

[bandcoach]

can you record some of the sound it is making?

my initial guesses are that it is either the fan has poor bearings and so causes the rumble or the power supply transformer is not properly secured and so rocks as the amplifier begins to work.

If the fan it needs to be replaced by a competent technician

If it is the transformer it needs to be reseated and secured properly (tighten the bolts/screws holding it in place)

it could be something else also

the crackle you hear is because the pots used in the volume controls are probably second rate or poor quality