Orion Xtreme 600.4 Buzzing.

[Chopperbuilder]

I have an old school Orion Xtreme 400.4. It powers up but produces a load buzzing sound through the speakers. Music is there too but barely audible over the buzzing sound. Only does it when the RCA's are plugged in. Already checked RCA cables, etc... They are not the problem. It is definitely something in the amp. Any ideas?

 

[Perry Babin]

Post a photo of the board.

Have you checked the shield ground of the signal source?

 

[Chopperbuilder]

I have. As I mentioned I've checked all other possibilities. I replaced the amp with a different one in the car and the buzzing was gone. I the took the buzzing amp and set it up on my test bench and it makes the buzzing noise there as well. It is definitely something within the amp causing it.

 

[Chopperbuilder]

Oh yeah, its not just a slight buzzing it is very loud.

 

[Chopperbuilder]

Upon a visual inspection I can see nothing wrong but maybe you'll see something I missed

 

[Perry Babin]

Measure the resistance from the RCA shield to the NON-bridging speaker terminals of the corresponding channels. What do you read?

 

[Chopperbuilder]

Reading is open.

 

[Perry Babin]

Are the shield grounds under the RCAs broken?

See attached if you don't know the location I'm referring to.

 

[Chopperbuilder]

That would appear to be the problem. Both shield grounds are broken. Do you know of a good place I can buy the type of RCA connector used in this amp?

 

[Perry Babin]

Mouser and digikey both have them, If I'm not mistaken.

Fix it temporarily to see if there are any other problems. See attached.

 

[Chopperbuilder]

I will do that and let you know the results.

 

[Chopperbuilder]

That solved the problem. Thanks for your help Perry.