Pickup demagnetising

[BurtMacklinFBI]

Getting a T-bird is totally awesome and everyone should do it.

Fixed that for ya!

 

[bert may]

I've been playing a jazz bass for decades. nothing happens to it. don't sweat you pickup magnets getting weak. you and your bass will be just fine

 

[nnnnnn]

Mine do, they're made by Monster Cable Co.

Oh, so they use peer-reviewed science... Carry on then.

 

[mikewalker]

The loudest pickup in my house right now is also the OLDEST... it's the Schaller humbucker that came stock in my 1981 Kramer Vanguard. Twice as loud as the very loud Duncan basslines in my Vaccaro X-ray. And I have five other basses here with EMG actives in them, and the old Schaller is louder than ALL of them.

Apparently its fine German magnets were precisely aligned with the earth's magnetic field in such a way that they actually grow stronger every year! Or something...

 

[farace]

Back when there was such a thing as a TV repairman, my dad had a horseshoe magnet (not the Rickenbacker kind, the Bugs Bunny kind). Being a curious kid, I wondered if it would have any effect, and I held it up to the TV screen. It didn't turn purple, but it kinda sucked half of the picture into that one little spot. I didn't know exactly what happened, but I knew I'd be in trouble for it, so I might have broke some kind of speed record turning the TV off and putting the magnet back where I found it.

When I was a kid my grandfather was a TV repairman, and he would come over every once in awhile and degauss our picture tube. He had a degaussing coil, a circular plastic ring maybe 8" in diameter that plugged into the wall and no doubt had many turns of wire inside, essentially a big electromagnet. He would turn it on and hold it close to the picture tube and move it in circles, starting small and getting larger as he moved further and further away from the tube, until he got far enough away that it had no effect, and he could switch it off. Made all sorts of trippy colors when it was up close.

 

[JimmyM]

When I was a kid my grandfather was a TV repairman, and he would come over every once in awhile and degauss our picture tube. He had a degaussing coil, a circular plastic ring maybe 8" in diameter that plugged into the wall and no doubt had many turns of wire inside, essentially a big electromagnet. He would turn it on and hold it close to the picture tube and move it in circles, starting small and getting larger as he moved further and further away from the tube, until he got far enough away that it had no effect, and he could switch it off. Made all sorts of trippy colors when it was up close.

My dad had one, too! They were great at clearing up bad color on TV's.

 

[Jeff Scott]

When I was a kid my grandfather was a TV repairman, and he would come over every once in awhile and degauss our picture tube. He had a degaussing coil, a circular plastic ring maybe 8" in diameter that plugged into the wall and no doubt had many turns of wire inside, essentially a big electromagnet. He would turn it on and hold it close to the picture tube and move it in circles, starting small and getting larger as he moved further and further away from the tube, until he got far enough away that it had no effect, and he could switch it off. Made all sorts of trippy colors when it was up close.

A bigger version of a tape head demagnetizer, but with a large ring instead of a small point on the end of it. (Does anybody remember tape? )

 

[farace]

A bigger version of a tape head demagnetizer, but with a large ring instead of a small point on the end of it. (Does anybody remember tape? )

I'm pretty sure I still have a tape head demagnetizer around here. (Still have a cassette deck. And an 8-track player/recorder. Somewhere in the basement are a reel-to-reel and a Fostex X15 four-track cassette recorder. No wire recorder, though. )

 

[RumbleMan3]

Be aware that strong little neodyme magnets are used in some unpredictable places like toys, iPad cover closing system. They can de/remagnetize Alnico if they get close enough. Mechanical watches can get magnetized easily with neodymes and it happens instantly.

Thanks for the warning

How can I tell if a particular magnet or object with a magnet is a hazard to my pups and to keep them a safe distance

 

[Luckydog]

Thanks for the warning

How can I tell if a particular magnet or object with a magnet is a hazard to my pups and to keep them a safe distance

Wrap your bass in 2” bubble wrap?

 

[okabass]

Thanks for the warning

How can I tell if a particular magnet or object with a magnet is a hazard to my pups and to keep them a safe distance

HI
Basically you can't. Strong enough magnetfield affects other magnets. I'd say that all neodymes are "dangerous". If you notice something has a strong magnet, don't let it closer than some 20 cm or 7...8 inches to the pickup.
Neodyme mags usually look shiny. And they are very strong, like some 5000 Gauss. Norm 7ender pickup Alnico 5 is max 1500 Gauss, usually 800-900 Gauss.
neodym magnet

 

[RumbleMan3]

HI
Basically you can't. Strong enough magnetfield affects other magnets. I'd say that all neodymes are "dangerous". If you notice something has a strong magnet, don't let it closer than some 20 cm or 7...8 inches to the pickup.
Neodyme mags usually look shiny.
neodym magnet

does my rumble amp have neodym mags? That's bad, cos I leave my bass right next to it all the time!

 

[okabass]

does my rumble amp have neodym mags? That's bad, cos I leave my bass right next to it all the time!

HI
I don't know. But you may know if it has. . If you keep that min distance - 20 cm or 7"... 8"- from the magnet field, you're safe.
I think some speakers have strong neos.

 

[MCF]

HI
I don't know. But you may know if it has. . If you keep that min distance - 20 cm or 7"... 8"- from the magnet field, you're safe.
I think some speakers have strong neos.

You should be using a stand to avoid it falling anyway which should keep it far enough away without giving it a second thought.

 

[RumbleMan3]

You should be using a stand to avoid it falling anyway which should keep it far enough away without giving it a second thought.

Yeah it is on a stand.

 

[JRA]

Here comes another 300 page thread!

and why not? what's not to like about a 300-page thread?

It's just my nature to be curious and often paranoid.

your paranoia can be de-gaussed...but you'll lose some curiosity in the process. i'm with all of those who are advising "not a thing"

so I might have broke some kind of speed record turning the TV off and putting the magnet back where I found it.

...right there with you! and my kids were just as fast as i was!

(Does anybody remember tape? )

running a studio: we had two giant plate degaussers to recycle 1" and 2" reels --- for rental to those who weren't interested in owning their tracks.

 

[BlueTalon]

does my rumble amp have neodym mags? That's bad, cos I leave my bass right next to it all the time!

You leave your bass next to it all the time, and you haven't yet experienced any of the things you say you fear? That should tell you something.

 

[byacey]

Pretty much all CRT color TVs had a built in degaussing coil that would degauss the internal shadow mask of the picture tube when the set was initially powered on. The manual degaussing coil was only really necessary if kids were playing with magnets on the front of the tube.

Magnets possess a property called Curie temperature where they abruptly lose their magnetism, but this generally happens 500F and higher, depending on the particular material, so I don't think the temperatures encountered in a boiler room would be responsible for degaussing the magnets, without char broiling the instrument.

 

[spoonman69]

I think I discovered why my late 60's Realistic violin bass suddenly had way low output..

Didn´t know that you have trouble with your Realistic. Thought your pickups are doing fine after repotting.
Maybe the pickups of my old Eko are suffering from demagnetising as well. I will see.

(But maybe I should have better post this in your Jay Turser thread? Don´t know...sorry..)

 

[JimmyM]

Didn´t know that you have trouble with your Realistic. Thought your pickups are doing fine after repotting.
Maybe the pickups of my old Eko are suffering from demagnetising as well. I will see.

(But maybe I should have better post this in your Jay Turser thread? Don´t know...sorry..)

It's fine...I saw it. And yes, the pickups sound great after repotting, but that was 7 years ago. And it could very well be wonky wiring causing the problem, since it's developed a ground problem recently. Taking it into my tech friend for some going over and a new zero fret, so he should be able to get to the bottom of it.