I hear voices. Please make them stop.

December 2, 2016 8:20 AM

I'm getting radio interference on my desktop monitors, and am assaulted by some sports talk show constantly whenever I'm not playing anything that would drown it out. As a result, I am reluctant to turn them on, and do so only infrequently, and am missing out on the full experience of shrooming dog videos on Facebook. They're Yamaha HS50s, connected to a Behringer mixer with 1/4" cables, and the power in my apartment is not grounded. Every time I try Googling this issue myself, I have a confused. Please tell me what to do to to fix this before I learn something about sports and/or throw the speakers through the window!
posted by univac to Media & Arts (12 answers total)

I have had this problem with my guitar amp in several places I've lived. It's definitely a grounding issue. You might be able to alleviate it by changing the positioning of the speakers or changing the wires around. I definitely was able to reduce this problem with my guitar amp by buying a fancy pants surge protector like they use in recording studios from Monster, but I'm not sure if that will work for your needs.
posted by pazazygeek at 8:38 AM on December 2, 2016

Response by poster: I do have a surge protector, though possibly not as fancy-pants as what pazazygeek recommends.
posted by univac at 8:43 AM on December 2, 2016

You might try throwing some ferrites on your cables.

It's possible the screw in the middle of your outlet plate is grounded. Buy a cheater plug, unscrew the screw in the middle of your outlet plate and screw it down the little grounding tab. If the screw is covered completely in paint scrape/sand it off (don't breathe the dust in case the paint is lead based).
posted by gregr at 8:55 AM on December 2, 2016 [3 favorites]

My partner has this same issue and ferrites fixed his shit right up.
posted by jessamyn at 9:00 AM on December 2, 2016 [1 favorite]

Yeah, the lack of grounding is kinda the first issue that should be considered, so strong second for gregr's idea. (In a sort of "close enough" technical explanation, most noise filtering & rejection works by "sending unwanted signals to ground & out of the main signal path", so having a ground point close to your gear is both safer and better for noise.)

But ferrite beads can also help a lot with hot radio signals.
posted by soundguy99 at 9:03 AM on December 2, 2016

Response by poster: About the "cheater plug" - I have 3-prong outlets, but the outlets are not grounded, according to my ground tester. Is there still a chance that the screw is grounded?
posted by univac at 9:18 AM on December 2, 2016

There is a chance the screw is grounded, but it might not be - probably not really. Try ferrite clamp cores.
posted by GuyZero at 9:19 AM on December 2, 2016

I have 3-prong outlets, but the outlets are not grounded, according to my ground tester.

This is pretty common in older buildings. The outlets were probably originally two-prong plugs, but a previous owner simply swapped-in three-prong plugs when electric appliances started coming with three-prong cords. It's remotely possible the screw is grounded (possibly, if an actual electrician did the plug swaps), but I wouldn't bet on it.
posted by Thorzdad at 9:24 AM on December 2, 2016

Response by poster: Actually, there is no middle screw - there are two screws on each end, and no way the cheater plug will reach. Ordering some ferrites now. Thanks, folks.
posted by univac at 9:24 AM on December 2, 2016

Response by poster: This is pretty common in older buildings. The outlets were probably originally two-prong plugs, but a previous owner simply swapped-in three-prong plugs when electric appliances started coming with three-prong cords. It's remotely possible the screw is grounded (possibly, if an actual electrician did the plug swaps), but I wouldn't bet on it.

I looked up the regs in my area and grounded power is not required in all rooms, so yeah, probably not grounded.
posted by univac at 9:25 AM on December 2, 2016

You're in Cook County, IL, right? You have metal conduit for all of your electrical wiring. The screw in the middle of your outlet should also connect to the metal box holding the receptacle. That whole mess should be grounded directly to earth at some point.

In my home there's a serious large wire and clamp that connects to the water supply connection (after the meter) providing ground for the system. At my mother-in-law's house (city of Chicago), there's a spike driven into the soil near the outdoor electrical meter.

Perhaps look around and see what type of ground connection you have from conduit to earth and check how secure it is?
posted by JoeZydeco at 9:34 AM on December 2, 2016 [1 favorite]

You should be feeding them a balanced signal. Either use the XLR inputs and or use proper TRS cables (not mono 1/4 inch cables). Whatever cables you use should be plugged into balanced outputs from your mixer.
posted by w0mbat at 2:34 PM on December 2, 2016 [1 favorite]