I had my stero up and running for a few months

it is 18" sub, longmill 2 channel 900 watt amp and a panasonic head unit

 

Fair enough

 

2 days a go i was driving and had it on quite loud and the the bass turned to farts (techie term) and it looked like a power drain

 

So i thought it could be the amp

replaced it and no difference ( but got a pulse noise every 2 seconds like some sort of feedback?)

 

so i replaced the sub

no different

 

i checked most of the wiring seems ok?

 

the bass works up to a certain point then just starts farting and it is not near its limits. it was working for months!

 

what could it be. the car seems to be charging as the battery as well

this farting noise is usually associated with a blown sub coil, u need a very power full amp to drive a 18, and a very high quality sub to cope, my mate blew a cheap 18 in about 20 minutes of buying it, also if the signal is very distorted it causes the cone to exceed its forward backward motion causing it to blow,

 

dont know what sort of music u listen to but i recon you would get a much tighter punchier sound with 2 x 10 or 12s at the most.

 

the amount of air a 18 incher is pushing is huge and requires any distortion in the signal is bad for it.

Burf,

 

Sounds like one of the power transistors has gone in the amp.

 

I assume you're running a multichannel amp in bridged mode for the sub?? If this is the case try connecting the sub to just one channel at a time to isolate a possible faulty channel.

 

If this locates the fault, it shouldn't cost too much to fix - ask around your local ICE dealers and see who they suggest.

 

Could also be the headunit - but this is less likely.

 

HTH

oops, just realised you said that you've already swapped out the amp.

 

Has to be a dodgy earth then... the pulsing noise is the amp powering off and on again.

 

Remove your earth, clean up the connector and /or use some abrasive paper to get a nice clean bit of metal

 

:rolleyes:

Dody earth yes, or dodgie battery possitive.

Ive had exactly the symptons you describe and it was how the +wire was screwed into my distribution block, not an adequate amount of the wire was clamped. When drawing lots o amps it matters.

Cheers people for your help!!!!!

 

This is a great forum!

Well my rear fog is connected to the same place and when i turn that on it make the car struggle more than i would expect?

 

i think its my earth or a short circuit somewhere!