Sub/Amp Install

Lou2 · 10-03-2011, 02:52 PM

Please help…I have searched and searched and can not find an end all answer. So please do not say this has already been answered in other posts!

I am inexperienced at upgrading sound systems in new cars and need a little help.

I own a 2007 BMW 328xi sedan (with under seat subs and door tweeters) and would like to upgrade the stereo on a relatively low budget.

1) What is the best way to add a subwoofer/amp to the stock stereo system.
I currently have a 12 inch Polk Momo sub and MTX Audio amp from my previous car that I would like to add)

What should I do with the stock subs under the seats? Leave them? Remove them? Replace them with another speaker?

What parts are needed to do this? LOC? Signal processor?

Finally, for the people that have done this. How does it sound?

MKR_DmD · 10-03-2011, 05:35 PM

There is a DIY in the Diy section. You do need a LOC.

People have been replacing under the seat subs with earthquake sws-8 aubs. I am going to be doing it shortly and powering them with an amp

carlos916 · 10-05-2011, 11:56 PM

NO LOC needed.. i didnt use one and im good.. all u have to do is tap into ur stock HiFi amp
Sub Left:
Red/White +
Brown/Yellow -

Sub Right:
Red/Blue +
Brown/White

and i the black thin wire is ur remote..

i dont have pics of the wires being tapped into the stock amp but if u need a pic for refrence let me kno i can can try to post one up!

VP Electricity · 10-06-2011, 03:29 PM

I suggest checking your Search settings. The defaults won't pull up the older posts where a lot of this has been answered.

LOCs do a couple of things. They attenuate and they isolate the signal ground.

Some amps can take the signal in from the Logic 7 woofer channels without an LOC. Most can't, and that means you hear distortion during bass peaks when playing it loud.

The best way to add the sub is to use Technic's harness. Not all MY cars have the same wire colors, by the way.

We use a modified version of Technic's harness in our sub-and-amp package, making the whole system ready to plug and play.

10-03-2011, 02:52 PM	#1
Lou2 Private 8 Rep 68 Posts Drives: 2007 328xi 6MT Join Date: Jan 2011 Location: NY iTrader: (0)	Sub/Amp Install Please help…I have searched and searched and can not find an end all answer. So please do not say this has already been answered in other posts! I am inexperienced at upgrading sound systems in new cars and need a little help. I own a 2007 BMW 328xi sedan (with under seat subs and door tweeters) and would like to upgrade the stereo on a relatively low budget. 1) What is the best way to add a subwoofer/amp to the stock stereo system. I currently have a 12 inch Polk Momo sub and MTX Audio amp from my previous car that I would like to add) What should I do with the stock subs under the seats? Leave them? Remove them? Replace them with another speaker? What parts are needed to do this? LOC? Signal processor? Finally, for the people that have done this. How does it sound?
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10-03-2011, 05:35 PM	#2
MKR_DmD Lieutenant 6 Rep 494 Posts Drives: 16 Jeep Cherokee Join Date: May 2010 Location: Germany iTrader: (3)	There is a DIY in the Diy section. You do need a LOC. People have been replacing under the seat subs with earthquake sws-8 aubs. I am going to be doing it shortly and powering them with an amp
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10-05-2011, 11:56 PM	#3
carlos916 Semper Fi 23 Rep 417 Posts Drives: E60 ///M5 Join Date: Dec 2010 Location: Sacramento iTrader: (1) Garage List 2008 E92 328i [5.00]	NO LOC needed.. i didnt use one and im good.. all u have to do is tap into ur stock HiFi amp Sub Left: Red/White + Brown/Yellow - Sub Right: Red/Blue + Brown/White and i the black thin wire is ur remote.. i dont have pics of the wires being tapped into the stock amp but if u need a pic for refrence let me kno i can can try to post one up! __________________
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10-06-2011, 03:29 PM	#4
VP Electricity Brigadier General 289 Rep 3,201 Posts Drives: F34 xDrive Join Date: Jan 2008 Location: portland oregon iTrader: (3)	I suggest checking your Search settings. The defaults won't pull up the older posts where a lot of this has been answered. LOCs do a couple of things. They attenuate and they isolate the signal ground. Some amps can take the signal in from the Logic 7 woofer channels without an LOC. Most can't, and that means you hear distortion during bass peaks when playing it loud. The best way to add the sub is to use Technic's harness. Not all MY cars have the same wire colors, by the way. We use a modified version of Technic's harness in our sub-and-amp package, making the whole system ready to plug and play.
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