There is a constant noise in our sound system and and is effected when we move our light Dimmers. We have narrowed it down to our house speakers, by during off the amp running to it. After we narrowed it down, we switched the lines that go to the house speakers, to another amp but it still made the noise.
So we think it's the lines running to the speakers but we wanted to know if there is anyway other way to fix this problem without replacing the lines.
Also we are getting noise from our media side mixer. We are getting a ground loop noise and we figured out it was from our Mac Pro but we can't figure out how to get rid of the noise.
Hope to here some responses
Sorry didn't notice the name thing :/
No it is NOT the lines running to the speakers.
First thing to do is to disconnect any
unbalanced inputs to the mixer, such as Cassette, CD Player, Computer.
If you have any outboard gear EQ, Comps, etc hooked up with unbalanced cables, replace them with balanced interfaces.
Does the noise go away? If so it is the unbalanced cable interface.
If not, disconnect one mic line at a time to see if it is an individual channel or input.
If it is isolated to one channel replace the cable. Still, there? Try tightening the screws on the XLR jack to get a better ground.
The mixer may not have enough Common Mode Rejection to differentiate the wanted from the unwanted signal. Try another mixer.
The cause is really the light dimmers. More than likely they are the cheap SCR type. These SCR dimmers actually turn the electrical wiring into broadcast antennae, in that they put the voltage and current out-of-phase and essentially couple with the electrical wiring. Usually the greatest buzz is right before they go out.
Proper dimmer paks are the solution.
On the Laptop, most are a problem due to the SMP or switch mode power supplies. Try using it on battery supply.