Damaaged speaker???

[bsco]

I have to post this....I removed this from a cabinet back a few weeks ago as the voice coil was completely seized...You wouldn't be able to move it if you hit it with a hammer...At the time I never noticed the magnet assy until after the fact...Just take a look......Hopefully I have attached this properly...If not i am sure somebody will correct me on the proper procedure...

[Enzo]

Your magnet is broken in two, it is history.

[bsco]

I realize that...but it is the first time I have seen one like this....and this thing is seized solid....

[Enzo]

It is seized because the magnet is free to move, now that it is broken free from the other half of itself. Your voice coil is pinched between the magnet and the gap wall. The center pole has slammed over against that wall, with the voice coil pinched between.

[The Dude]

Of course it's seized. When speaker magnets break or the glue lets loose between magnet and basket, the gap shifts binding up the voice coil. Broken magnet structures are not all that uncommon- usually caused by the cabinet being dropped. In fact, without even taking a speaker out of the cabinet, you can usually identify a broken magnet or shifted gap by noting that the voice coil is seized.

A word of caution: Do not try to pry it apart with your fingers. These magnets are very powerful. If you do, you'll find out in a hurry why I say this. If you are interested in seeing the inner workings of the speaker and finding out why it seized, pry it apart with a screw driver or two and see why the break caused the seizure.

[bsco]

I guess you guys have replaced a lot more speakers than I have...this is the first time I have seen it....I wasn't planning to take it apart.....I just posted the pics...Thanks for the cautionary warning anyway.....
Cheers,
Bernie

[gbono]

someone doesn't play nice with their toys. The second image looks like something cleaved the side or maybe the magnet went into compression from a cabinet drop - though you probably would notice a damaged panel or corner.

[bsco]

To tell you the truth...there was no signs of damage on the cabinet....you think there would be......but this is what the speaker looked like after I took it out......something caused it to crack and it is cracked all the way around....

[Enzo]

Oh there are lots of fun firsts. Wait until your first little electrolytic cap goes off like a 22 round and shoots past your ear. That's exciting.


The magnet is ceramic they can crack or shatter. In fact they can also flake off, and some of those flakes can be VERy sharp edged.

Instead of prying it apart, try this: use an Xacto or a razor blade and just cut the dust dome off the center of the cone. Now you are looking right down into the magnet and voice coil. You should be able to see the center pole is now pinched over to the side of the gap. The "gap" is that circular slot the voice coil rides in.


I'd believe the sppeaker was dropped. it may have landed flat so no corners were dented.


Sometimes I hear something rumbling around in a speaker cab, complaint is no sound. I open it up and find the magnets sheared completely off the basket frame, and rolling loose in the cab bottom.

[Strikerj]

Wow looks like a earth quake hit the magnet.
Must have been something when it went.

[bsco]

I'll have a look at that Enzo...Thanks for the tips....
Strikerj....something happened to it...I never had the pleasure of witnessing it though.....

[Sowhat]

I love insanely damaged parts, I'll hang them from the wall, the make great conversation pieces. :-)

[The Dude]

......and, in this case, great for magnetizing screwdrivers.

[bsco]

Hahahaaa...hey guys...never thought of that...maybe I will hang it on the wall....it is a conversation piece for sure...it will probably be a long time before I see this again...
I can even stick my screwdrivers on it and won't misplace them...

[gtrplayr1976]

Oh there are lots of fun firsts. Wait until your first little electrolytic cap goes off like a 22 round and shoots past your ear. That's exciting.

Thanks..that kind of makes me not want to work on amps anymore