Help: Trouble with amp + sub installation.

[Kcc]

I have an old Sony amp + sub from my previous car and did the installation last week on my 2011 135i. The trouble I am having is "single" problems as the installer has told me.

The visible problem are the sub gets continuous low volume "bass" once the car started even with the OE head unit turn off (sound like...ummmmmmmmmm...). The installer said he gets the signal from the OE sub under the seat into the amp, which he had try different amp and sub with the same wiring and same problem occur. Also, he had try using another speaker connect the signal directly to the OE under seat sub, which same ummmmm sound.

What I need to know, how do I solve this problem? I did not upgrade my stereo, so I am sure it's not logic7, but not sure if it's hifi or top hifi.

I also know Sony amp + sub are cheap and they are totally big different from the JL, but I don't want to waste it since I have them for 4 years and it still works fine. (Altho I want the JL, but maybe later)

I saw some post about JL cleansweep, not sure what they do, maybe it could solve the problem? I am only penis sized once it comes to audio.

Please help me out, thank you!

Kcc

[3onDubs]

Not necessary to go to the sub under the seat for signal, grab it from the amp (in the trunk or rear seat quarter panel if you have hk)....

Read this (and forward it to your installer): http://www.1addicts.com/forums/showthread.php?t=334350

[Kcc]

Thx, but I don't know what other things they have tried...also, I am not sure if 2011 have any different from previous model. The installer had gave me a refund, so should I change the installer? They said they had install alot of BMW 3 series, but don't know why it doesn't work for the 1 series...That's what made me worries if there's any changes to the hifi system. I don't wanna go back for the install, and same thing happens...

Kcc

[kmarei]

if you have HIFI the head unit the headunit puts out a balanced signal
maybe the amp does not accept a balanced signal?

do you know the model of the amp
another way to test is to hook up an ipod to the amp
using a stereo mini jack connetion to 2 RCAs that go into the amp
if the amp still makes the ummmmm sound then the problem is either in the amp or in where you are getting power from.
if it works then the issue is the balanced output of the headunit
i believe there are some units that convert balanced to regular unbalanced
if thats the issue i'll search for some units that have been recommended on these forums

[Technic]

Depending on the 2011 production date, this is either a Stereo or a HiFi system.

If there are no tweeters in the front doors then it is Stereo.

Once this is answered then possible causes and solutions can be given.

[Kcc]

Tweester are the one right beside the side mirror? Like a 1.5 inch speaker? If that's the case, I do have that tweester! Please help me out! Thx!

Kcc

[mineo77]

i think you may also have an 'installer' problem. Send VP Electricity a note, he may be able to help...but he is crazy busy with his own customers so may not get back to you for a bit.

[Technic]

Originally Posted by Kcc

Tweester are the one right beside the side mirror? Like a 1.5 inch speaker? If that's the case, I do have that tweester! Please help me out! Thx!

Kcc

Did your installer used any converter before the Sony amp?

[Kcc]

What is a converter? A thing before the RCA into the amp? Yes if that the one.

Kcc

[Technic]

Originally Posted by Kcc

What is a converter? A thing before the RCA into the amp? Yes if that the one.

Kcc

Do you know if the converter is differential input, like this one? http://www.myradiostore.com/noise-fi...pdc-locv2.html

[Kcc]

Originally Posted by Technic

Do you know if the converter is differential input, like this one? http://www.myradiostore.com/noise-fi...pdc-locv2.html

If it's differential, than I don't know, but did have something like that...but cheaper looking.

Kcc