What is happening to this subwoofer?

[SGunnem 51]

I have been wondering and I have to ask what is happening here?

What is causing the sparks?

What exactly am I looking at?

Thank you.

 

[nem 2,019]

Almost looks like a copy of the super gauss motor with a vented poll. Not sure though.

[Duran 387]

Looks like an SMD prototype or something.

[jonbearsmt 919]

i have seen these before,

 

 i didnt seen any sparks but i can tell you that the former on those things are around a foot long.. very hard to control. im sure there is a bit of walk in the gap. and it may be touching the motor causing sparks.

[Dictator 39]

wow that was just weird looking.