Amp "bumping" when turned off

Sun Mar 06, 2005 1:10 am

Whenever I turn my amp off (via a remote wire from the head unit) I get a loudish bump from my rear 6x9's (the only speakers connected to the amp).
Is there any way to stop this?

Sun Mar 06, 2005 1:22 am

check that the amp is well earthed (bare metal-preferably held onto the body with a nut or screw)

Cheak that the remote off wire is connected correctly at both ends

make sure that the amp's gain level isnt too high (I generally run mine at no higher than 1/2)

check the connections between amp and speakers are firmly connected using good quality (oxygen free) wiring

good luck

Neil

Sun Mar 06, 2005 1:29 am

Thanks for the reply. I've got the gain at about 1/3, I find thats plenty. The remote seems ok - I'm using the same wire for the electric aeriel but I wouldn't have thought that makes a difference, it still bumped in my previous car with the remote going straight to the amp and nothing else. I haven't actually got the amp earthed though - the only connections are the remote, +ve and earth power, imputs from the head, and the speaker ouputs.
I'll see if I can earth it somewhere tomorrow and see if that makes a difference - it has got a connector for earthing but I thought that was just for when I was using high level inputs...

Sun Mar 06, 2005 12:58 pm

I always earth my amps as it ensures a good circuit!try that and good luck!

Sun Mar 06, 2005 5:11 pm

yeah you realy need to earth your amp, if you can use the same size wire as the live feed to your amp, and try to earth it on some nice metal

Mon Mar 07, 2005 12:23 pm

It would also help to turn the head unit off before the amp, so hopefully no signal is going to the speakers.

Does the remote have a volume control or even better, a mute button?? If so, turn the volume right down or mtue it before switching it off too.

Perhaps a capacitor based protective circuit may help? Not sure how to configure etc but capacitors are generally used to protect against spikes.

Mon Mar 07, 2005 12:26 pm

blatantarrogance wrote:It would also help to turn the head unit off before the amp, so hopefully no signal is going to the speakers.

Does the remote have a volume control or even better, a mute button?? If so, turn the volume right down or mtue it before switching it off too.

Perhaps a capacitor based protective circuit may help? Not sure how to configure etc but capacitors are generally used to protect against spikes.

Just reread your question and I think I misinterpreted "remote". Try killing the volume by one means or another perfore powering down.

Mon Mar 07, 2005 1:44 pm

It doesn't make any difference. I used to have the amp switch on/off by a seperate switch providing 12v to the remote connector on the amp, and it still bumped with the head unit on or off.
I was thinking about using some sort of capacitor based protective circuit but I don't know how to wire it up, or whether you could actually just buy something that would connect up and do the job?