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Author Topic: Speakers causing discoloration, help.  (Read 624 times)

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piscian18

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Speakers causing discoloration, help.
« on: August 29, 2019, 10:37:06 pm »
Oddball question, the original speakers in my cabinet are causing discoloration in the corners of my screen. I read somewhere its the magnets. Does anyone have any advice on how best to shield them? or properly shielded replacements?

buttersoft

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Re: Speakers causing discoloration, help.
« Reply #1 on: August 30, 2019, 02:59:56 am »
Shielding them will be a pain, and pretty expensive to do properly. You can try cutting up a pair of PC speakers, those often give pretty good bang-for-buck.

If your cab is still running jamma, you might have to go to local shops testing. Get a magnetic field sensor app for your phone - anything under about 80uT at the distance from the monitor to the speakers is good.

The problem might be that when you remove the old speakers, you'll find out the tube has been magetised for so long the purity can't be corrected by degaussing. If so, you can try some small disc magnets in the affect corners around the outside of the tube. Or you could leave the original speakers there and try this - you could even start with fridge magnets in this case.

BadMouth

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Re: Speakers causing discoloration, help.
« Reply #2 on: August 30, 2019, 01:30:57 pm »
Parts express usually has shielded speakers for a decent price.  They buy out old factory stock of TV speakers.  Paying for shipping does suck when only ordering a couple cheap things tbough.

Move the speakers away from the screen now.  The longer they stay close to it the more likely you'll need a special tool to get rid of the discoloration.

piscian18

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Re: Speakers causing discoloration, help.
« Reply #3 on: August 31, 2019, 05:08:16 pm »
Parts express usually has shielded speakers for a decent price.  They buy out old factory stock of TV speakers.  Paying for shipping does suck when only ordering a couple cheap things tbough.

Move the speakers away from the screen now.  The longer they stay close to it the more likely you'll need a special tool to get rid of the discoloration.

Yeah I pulled the speaker causing the distortion, pictures fine, thanks thats actually perfect, they have the exact one I need.

On a sidenote. I see a whole lot of posts online with cabinets having the same distortion in corners. I only knew what my issue was because I was pulling parts in and out of the cabinet. I wonder how often its really just undiagnosed magnetic interference from bad speakers.
« Last Edit: August 31, 2019, 05:14:56 pm by piscian18 »

BadMouth

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Re: Speakers causing discoloration, help.
« Reply #4 on: August 31, 2019, 08:02:50 pm »
I never thought about younger people not knowing about the effect magnets have on CRTs.  For those of us that grew up with CRT TVs, it's something we figured out  as kids when we put stereo speakers too close to the tv.