problems whit aftermarket in a 2008 volvo

[Martin Eriksen]

I have an annoying problem! Installed an aftermarket subwoofer and amp. Sometimes it seems like the sub has its one life just make noise. And when i turn off the car it makes noise. I have a hi to low converter that i think is the problem. i had an amp whit a hi input an it worked perfectly (no noise). Whatever i do it won't work properly, and when i open the trunk it stops making noise. When i turn up the potentiometers in the converter it makes more noise and to get no noise i got no bass. Help please!!!

[Ray]

Where did you grab remote turn on?

[Martin Eriksen]

on the original amp. i tested it. it holds on the power in 10 sek or so. but it worked wen i had the other amp whit hi input :S

[zxsonnyxz]

I think you should try to explain more detailed how and when the problems occure, and what the sound is like.

A friend of mine have a 05 V50 with the "Performance" system in it. This might not be the exact same situation as yours, but similar:

We installed an Alpine integration type prosessor to get signal for the sub amp, an it had the same problem. The prosessor have hi-level inputs and an automatic turn on feature (as well as a remote turn on, but I don't think it affected anything in this case), and with this particular setup I think that's part of the problem. We noticed after installing it that it turns on almost by witchcraft, even when just opening one of the doors iirc. And as we got the remote turn on for the amp from the prosessor, the amp turns on aswell. If you got in the car and closed the door or hit it with your hand, you would get a ringing sound from the subwoofer. That is until he turned the ignition and the factory hu turned on. No noice.

I didn't get to play around with it so much, and now he is selling the car so it's ripped out, but i have a plausible theory on the cause of the problem. Maye Ray here could tell if it's even possible:

Speakers work by sending power to a coil that makes a magnetic field that in turn reacts with that of the magnet. Also, if you add external force and move the coil up and down the magnet gap, maybe caused by movement and vibration as you move the door or when the metal of the door and the speaker itself resonates as you hit it, the magnet will induce voltage in the coil, and you have an electrical signal coming out of the speaker. Now, if your hi-level prosessor is connected to the speaker wires on the amp, and is made to turn on when it gets a signal from the amp, it could also turn on from the signal from the speaker, right? Asuming it's strong enough. And as the amp turns on with the prosessor that signal wil get amplified and ran through the subwoofer itsself and you get that noice. And if you where to have enough power to the woofer, the pressure from the woofer (DD 15" in this case) would affect the the speakers and complete the circle of feedback that he got when the gains where turned up.

This is all until the factory amp turns on and consumes (dampens) these sorts of noises in the system. And it works great when it's actually playing songs.

My plausible theory, maybe someone ecperienced can chime in..

I have also read that many of the hi-low converters are bad quality so it might just be that, or maybe a combination.

Btw, Martin Eriksen høres veldig norskt ut?

[Martin Eriksen]

takk hjalp mye

har du noen ide på hvilken måte eg kan få vækk den satans lyden ^^