Speaker magnetic inteference?

[GILow]

Hello Cruisers,

A while ago I pulled out the very tired old set of massive speaker boxes in the cabin, and consigned them to land fill. Chipboard boxes do NOT look good after 20 or so years.

Now I am about to replace them with something a lot smaller, but I am worried about interfering with the compass or either of the fluxgate sensors on the boat.

Is there a rule of thumb for how far away these should be from the speakers, if the speakers do not have any special shielding?

Matt

[Lake-Effect]

I would aim to have speakers at least 2 m (6.5 feet) away from the helm compass and fluxgate compass sensor.

But it's easy to confirm whether you're getting interference... make note of your compass readings, then bring the speakers aboard and check for changes. You can also try moving the speakers toward the compass to see how much influence the speaker has and at what distance. Or test with a pocket compass.

Does anyone still "swing" their compass, or pay a pro to do so? That's the gold standard for detecting and factoring out any remaining magnetic influence.

Good "shielded" speakers are still available - look at some of the small monitor speakers sold for home studios, for example.

[highseas]

I had shielded marine speakers mounted in cockpit(bad idea,PO).I routed my longwire GTO cable near speakers ,as was nowhere else to run it.When I removed speakers ,my SSB reception improved dramatically.

[GILow]

Originally Posted by Lake-Effect

I would aim to have speakers at least 2 m (6.5 feet) away from the helm compass and fluxgate compass sensor. But it's easy to confirm whether you're getting interference... make note of your compass readings, then bring the speakers aboard and check for changes. You can also try moving the speakers toward the compass to see how much influence the speaker has and at what distance. Or test with a pocket compass. Does anyone still "swing" their compass, or pay a pro to do so? That's the gold standard for detecting and factoring out any remaining magnetic influence. Good "shielded" speakers are still available - look at some of the small monitor speakers sold for home studios, for example.

sounds like a sensible approach. Certainly easy to do in the marina too. Our main compass was last calibrated about 10 years ago but before that it was done every couple of years by the original owner. I guess gps has changed how much importance people attach to the compass.