DC offset spike?

[Rask717]

Hi,

A few days ago, I accidentally damaged one of the speakers of an audio system (Edifier S730), most probably because of a loud and high-pitched distortion (noise?) that happened when the system was connected or disconnected from my computer while turned on.

The sound is difficult to describe, but one knowledgeable person I asked replied that it was a full volume DC offset spike. Is this the actual technical term? If so (or not) is there a way to prevent it in the future (besides being really, really, careful?) Electrical problem? The set was directly connected to a wall socket. However, the other is full of power bars connected to a computer, two routers, three monitors, and an external HDD.

 

[giantbucket]

it's possible that the voice coils are burned on that speaker OR they popped out of the gap. if you can put your fingers gently on the speaker cone, try to push it - gently. if it isn't moving at all, the voice coil probably popped out of the gap. if it's scratchy, the voice coil is burned.

the only way to prevent it is to ALWAYS turn on the speakers LAST, and ALWAYS turn off the speakers FIRST (and work your way through the signal chain in that manner).

DC offset spike may be an ok term for it, but that's besides the point. it's not an electrical problem per-se, just a fact of turning on anything electronic - it takes time for everything to stabilize, even if it's just a few milliseconds.