"blown speakers"


When a speaker "blows" what actually happens. I suppose its different between a tweeter and woofer, but is there some mechanical damage or is it electrical. does something break? Besides a woofer cone ripping, what happens to a tweeter if it is still working, but raspy or staticy? I have heard "blown" speakers before, or ones that didnt work at all, but I really dont know what it is that breaks and whether it is fixable or just replace.
manitunc
generally caused by a amp being pushed into distorted clipping and this generates heat in the speakers voice coil ruining it eventually. just a laymans definition. they can also catch fire....
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Is there a way to test the speaker to see if there is a problem. The reason I ask is that in one of my speakers, when playing very loud, I heard a sudden rasping sound.When I reduced the volume, it sounded ok. It can still play quite loud without the rasping sound, but I dont really want to play it again as loud as it was to see if the sound comes back. IT was really loud, Pink Floyd Dark Side of Moon, Money. Quality amp of 275 watts, playing vinyl.