Need help fixing a solid state subwoofer amp

[gayler]

Hollo all! I have a sub amp for home theater that makes a loud buz. It also has the bass coming threw also but the buz is louder than the music.I'm thinking maybe a cap in the power suppy. What do you all think?

[Enzo]

Disconnect the input to it completely, now does it still hum? Poor input connections can cause hum, so we want to elimiate that possibility first.

Then if the amp is indeed at fault, open it up and check for excess ripple on the main power supplies.

[gayler]

Thanks Enzo!I did this a while back and as I remember there was no hum, but I can plug in a different amp with the same cable and it doesn't hum.

[Enzo]

The point is that if the amp was blown or had filter cap problems, it would sit there humming all by itself.


You may be able to connect the signal to some other amp and not have hum, but that doesn;t rule out a bad ground connection on the input jack of this unit, for example. Once we know the amp itself doesn;t seem to be generating this noise, we start looking for things like that.

If the input connection were faulty, I would then expect the volume control on this sub can turn the hum volume up and down?