Bass thump on shutdown

[esha]

OK, ive just installed a new sub and amp in the motor and am having a little bit of a problem!

Firstly I just rigged up the sub (FLI 1000w active sub) without the amp or 6x9's, everything fine with thumping bass, groovy!

Now, Ive rigged up the amp (Mutant 2channel 1000w i think!) and everything else, used a proper junction box to split the power from battery to amp and sub etc etc, but now when i turn everything off I get a thump/pop from the sub.

No matter how I turn everything off, turn HU down then off then switch ignition off, I still get the pop and i dont think its doing the sub any favours! All the leads are connected as they should be, BUT, in my haste ive left everything a bit messy, could it be a simple case of the wires are to close together and is causing interference or am i barking up the wrong tree? My bro had a thought that it could be power surge and i should try using a slave battery, which is obviously completely impracticle!

Any ideas would be greatly received as at the moment im thinking of disconnecting the sub before I turn the ignition off!

 

[ollyc98]

You need a soft cut system, where the power suddenly drains you get that pop, I had my on remote on a separate switch so I could switch off the sub then the stereo

 

[esha]

You need a soft cut system, where the power suddenly drains you get that pop, I had my on remote on a separate switch so I could switch off the sub then the stereo

Soft cut? no idea what one of those is, although it sounds obvious! Would the power cable plug into this then into the sub? Or would everything plug into it i.e remote, power, ground then these into sub?

 

[Antony]

usualy i have found this to be a setting on the amp itself.

i worked for halfords as the ripspeed audio specialist for 5 years and have fitted hundreds of these mutant amps.
they do pop, partly cos theyre not very good and partly because of the internal achitecture. not sure what causes it but if you turn the amplifier off before the stereo it will stop.

there realy isnt any way around it with a mutant.

you can simply wire in a simple switch to the remote switch lead (usualy blue thin cable)

 

[esha]

yea i went for a mutant simply cos i dnt have a lot of cash to spend. As ive got the remote wire going into amp then fed to sub, do i just cut the wire somewhere near the HU then add a switch in? and what do i use, ive got next to no knowledge about electrics so i dont know how to do any of that, i had to draw myself a diagram before i attempted the install, and i was constantly worried about something going bang!

 

[Antony]

the wonderful thing about car electrics is that they are all fused. so dont worry.

yeah, if you cut the blue wire near the head unit and simply wire in a switch, a two pole on off switch is your best bet. or an aircraft style rocker switch.

 

[Retepetsir]

Try re-doing your earth, or fitting a seperate earth for the Mutant amps. Cheaper amps tend to have no soft turn-off feature, or a poor quality one. A decent earth quite often fixes the issue.

 

[esha]

Ok well thanks for the help guys, ill see what I can get hold of in the next few days, wish it could be sooner as i dont like the sound of the pop but work always gets in the way!

For the earths, ive used the bolts on my boot release catch, not the same one for both but theyre both earthed on that catch, should i move one of the earths to a different place? I think the on/off switch on the remote wire sounds easiest so ill try and find one soon, thanks for the help!