6x9 problems

[mouthyman]

i have some 400w rear 6x9's, they were working fine until i got my car bhack from its MOT now there is a vibration at any bass tones and they are distorted.
any ideas what it could be?

 

[Loopy]

Is it happening on both speakers or just one. It could be that the voice coils have burnt out from being turned up to loud or driven to hard for too long, you can check this by pushing down on the speaker cone, if it feels like its grinding or smells burnt then that could be the problem

Another possibility is that you have speaker wires crossing (touching) together or one of the cables has been nicked and its going to ground. This creates a feedback to the Head Unit amp and it will distort

Or god forbid its not but it could be the amp in the head unit

 

[mouthyman]

i dont think its the amp because the other speakers work fine, i havent run it for longer than about 10 mins as ive only just fitted the headunit,
i have the problem on both speakers but they shouldnt have burnt out as they are running at around 45w off the headunit at the moment but they are 200w speakers.