Radio signals coming through my cables?

[frenziedsilence]

I'm sorry if this question doesn't belong here, but I'm new and it seemed like the best place.

We just moved our music room to the other end of the basement, which has bare concrete floors, unfinished ceiling with sound-blocking foam on the ceiling & walls, and metal air ducts.

Suddenly, in this new room, the microphone is picking up an AM radio station! Currently the mic is going through a Vocalizer and into the mixer. Putting a hand on the microphone itself amplifies the signal. When we pull the 1/4" cables connecting the Vocalizer to the mixer out just a little, the radio signal gets even stronger.

Does anyone know why this is happening, or how to block the radio waves? We can't record like this!

Thanks.
-Kathryn

 

[Blue Bear Sound]

Definitely a grounding/sheilding problem..... you may have to get a local wiring company to check out how you've got things wired-up!

 

[boingoman]

Definitely a grounding/sheilding problem..... you may have to get a local wiring company to check out how you've got things wired-up!

There is a little radio shack dealie you can get- an outlet tester. It'll tell you if your outlets are wired correctly. It's pretty cheap. I'm just assuming you have three prong outlets. If not, get one of those three to two plug adapters and plug it in. be sure to use the ground tab! it gets connected by unscrewing the screw in the middle of the wall plate, plugging in the adapter, and putting the screw back in through the tab. Making sure your power is right and grounded is the place to start, for safety if nothing else.

I'm not sure what the Vocalizer is. Brand? If it has balanced ins/ outs and so does your mixer use balanced cables. That will help some. And check that mic cable and mic- sounds like there could be a loose wire somewhere.

There are things called power conditioners which mount in a rack and have outlets to plug in your gear. They have built in radio frequency and EMI filtering.

With troubleshooting I generally start with the simple and cheap and work up from there. Check your cables and power first.

 

[Coolster]

Are you by chance using a Mackie mixer? We had the same problem at church on occasions when our sound man got his own Mackie 32-8 and wanted to try it out. Luckily it was another church broadcast that we were picking up, instead of Metallica or something. Anyways, he found someothers had the same problems with the 32-8?

 

[bennychico11]

Make sure you're using balanced cables first off (although, I'm assuming you are if you're saying it's doing it on the microphone too). The reason it's amplifying when you touch the mic is because your body is acting like an antenna. And same things Blue Bear said...grouding/shielding. Try some other cables that might be around, checking to make sure that you're using shielded cables. Also make sure you're keeping audio cables and power cables separate or crossing them at 90 degrees. Good luck.