Magnetic shielding for near CRT speaker placement

[hoffsta]

Hey there, I'm working on a jukebox multimedia project built inside an old 80's console TV. I posted many details over here in the Construction tips section if you'd like to see.

Basically, I'll be significantly upgrading the audio system and I'm worried about what kind of magnetic shielding I'll need as I plan on installing tweeters/mid drivers within about 6" of the CRT tube and some sort of woofers about 12" away.

Here is a photo of the cabinet:


tweeters/ mid drivers will be mounted on the front panel on either side of the CRT and I am considering a 10" sub in enclosure mounted in the lower left and firing out the side.

Any thoughts on how to shield for this setup or recommendations on inexpensive shielded speakers? I saw some material called mu-metal but it's very pricey. On my budget I was thinking of drivers from parts-express but I'm open to ideas. Thanks!

[weltersys]

Originally Posted by hoffsta

Hey there, I'm working on a jukebox multimedia project built inside an old 80's console TV. I posted many details over here in the Construction tips section if you'd like to see.

Basically, I'll be significantly upgrading the audio system and I'm worried about what kind of magnetic shielding I'll need as I plan on installing tweeters/mid drivers within about 6" of the CRT tube and some sort of woofers about 12" away.

Here is a photo of the cabinet:


tweeters/ mid drivers will be mounted on the front panel on either side of the CRT and I am considering a 10" sub in enclosure mounted in the lower left and firing out the side.

Any thoughts on how to shield for this setup or recommendations on inexpensive shielded speakers? I saw some material called mu-metal but it's very pricey. On my budget I was thinking of drivers from parts-express but I'm open to ideas. Thanks!

I used to have a pair of big magnet drivers below my CRT TV, a piece of 1/8" by 6" x 12" iron was adequate to prevent screen distortion.
Scrap steel is cheap.

In your set up, rotating the individual drivers so the stray magnetic force tends to cancel out may do the trick with no shielding needed.
In retrospect, I should have tried that, but I had the iron laying around the shop, laying a piece on top of the finished cabinet was a quick fix.

P.S. My speakers were only about 2" from the CRT.

[hoffsta]

Good to hear about your setup! I assume the sub will put out considerably more EMI than the smaller drivers. I guess I'll just have to try it all out...

[weltersys]

Originally Posted by hoffsta

Good to hear about your setup! I assume the sub will put out considerably more EMI than the smaller drivers. I guess I'll just have to try it all out...

You can experiment with the speaker angle with the sub, no need for a sub speaker to be straight up and down.
At a couple feet away, fairly large magnet structures had no effect on my old TV (since donated to Goodwill). The same speakers at 1" to 6" made a big effect (looked cool when drunk ), fortunately the screen came back to normal after powering up and down a few times .