Just a quick question for those of you who have a sub + amp install in the boot...

1st of all, i was told by my local car audio shop that the head unit in the E55 (i have the normal head unit with 6 disc changer, and phone, not sat nav) does not have RCA outputs...

so what they did is tap into the rear speaker wire to create a signal there, and used some sort of box to change this to a phono connection for the amp...

Now my problem is this - there's a lot of interference coming through when i put the volume up - turning the subsnic filter on helps, and keeping the filter at a low frequency also helps, but it still sounds rubbish...

The amplifier (a digital 1000w alpine v12 amp) is in the spare wheel well, so i think it might have something to do with the battery being right next to the amp, so causing some interference..

Also - how the hell do I secure the sub?? It keeps moving around cos the carpet that covers the spare wheel well isnt fixed!

Long post I know, but thanks for any info!

 

BUMP

surely someone must have an answer?

 

I don't have that issue with a JL 12" W3 sub and JL amp. The signal comes from the rear speaker feeds and the amp is bridged for a single output. It works great. I'm guessing the amp doesn't like the signal, it's not where it's mounted. "Some sort of box" is probably bad or doesn't match the amp.

 

What your audio shop have probably done is used a speaker signal to rca converter......interference can sometimes be reduced by adding a line driver to increase the voltage output thus resulting in a cleaner signal being sent to the amp.

The other solution would be to try the JL Audio clean sweep (most peoples install of choice).....the clean sweep does the same thing but should be interference free???

By the sounds of things.....your audio shop doesn't sound too hot......I would have thought securing the sub box would be easy stuff for these guys??? perhaps some kind of velcro strips could be used???

....the hottest installers I can think of would be Braybrooks....www.braybrooks.co.uk, they done an install on my previous E55....they offer a very proffesional service.

....I have been thinking of installing a sub in my car too......but I was looking at having a custom box made which would be strapped to the back shelf.......and fire directly into the car through the existing hole where the current sub is situated.