Replacing Subwoofer....? -
LinkBack Thread Tools
post #1 of 5 Old 03-28-2007, 03:54 PM Thread Starter
Registered User
Join Date: Mar 2007
Location: FL
Posts: 5
Replacing Subwoofer....?

i have a 07 jeep compass, limited, with the 9 speaker boston acoustics system..

pretty nice, the speakers themselve sound crisp, but the subwoofer is near basic..

i was wondering if i can remove the subwoofer and replace it with another subwoofer component, or, is it better to buy the entire enclosed box and speaker to take up space in my trunk?

thanks in advance..

Lay-Z is offline  
Sponsored Links
post #2 of 5 Old 03-28-2007, 04:01 PM
The Necessary Evil
Gramps's Avatar
2007 MK Compass 
Join Date: Aug 2006
Location: Madison/Janesville
Posts: 5,624
Maybe you need to talk to Jason31. Here's the tread that he started. Hope it helps.


Artificial intelligence is no substitute for natural stupidity

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
posts 68 & 69

Also visit me at
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

'06 WK Grand Cherokee Limited Quadra-Drive II, 5.7
'07 MK Compass Limited 4X4, AutoStick
Gramps is offline  
post #3 of 5 Old 03-28-2007, 04:03 PM Thread Starter
Registered User
Join Date: Mar 2007
Location: FL
Posts: 5
ok, i see.. but what he did was connect up a enclosed subwoofer to his system, not really replacing the actually 8in sub that boston used..
Lay-Z is offline  
post #4 of 5 Old 06-10-2007, 09:45 AM
Registered User
snood's Avatar
2007 MK Compass 
Join Date: May 2007
Location: New York
Posts: 127
did u ever replace it?

'07 Compass -> I apologize to the next owner.
snood is offline  
post #5 of 5 Old 06-11-2007, 01:49 PM
Registered User
Join Date: May 2007
Location: West Chester
Posts: 127
I posted up this in another reply, but may be pertanent as people search this thread out in the future:

Maybe I can help a little bit. In my more youthful days, I participated in audio competition.

The short:

Subwoofer- What is the depth of the JL? What is the width of the JL magnet and coil assembly? What is the depth and width of the subwoofer housing on the Jeep?

If JL Subwoofer Depth and Width < Subwoofer housing Depth and Width, Subwoofer will fit physically.

Amplifier- What is the load ratings on the stock amplifier? What is the load rating on the new subwoofer? (unless gramps can look it up for you, the best place to check is probably to remove the factory subwoofer, and look at the back. Typically it is printed on the sub). It looks something like a *Number* followed by a *greek omega* (horseshoe looking thing) that represents "Ohms". if this information is not available, get the model number off the sub and look online for information on it regarding load (ohm/omega symbol) and wattage.

If you luck out, and the Ohm rating of the factory sub is the same as the rating on your JL, it will will work in there. * <- see star below. If its not the same, you need to fine what loads the amp can support.

Wattage is potentially a problem as well. What is likely to happen is that your sub could work, but the factory amplifier cannot put out enough power to offer the subwoofers full potential. If this is true, you need to install a new amplifier. If you do not, and run the factory amplifier at above-typical power, then it will introduce distortion, which will blow your subwoofer.
The reverse is also possible. The amplifier COULD output more power than the subwoofer can handle. Turning the amp all the way up could blow the subwoofer.
While I'd say "look at the wattage ratings of your subwoofer and the factory amplifier", this presents a problem. Stock components are typically very conservatively rated, while aftermarket accessories (such as your JL) are typically exaggeratedly rated. Take the ratings with a grain of salt, and look for RMS, not peak power ratings.

*- Some subwoofers are DUAL VOICE COIL. if your subwoofer is DVC, then you need to think of it as TWO SUBWOOFERS. If each coil is 2 ohm, then depending on how you wire it, this subwoofer can be either 1 ohm or 4 ohm... but NEVER 2 ohm. If the factory one is 8 ohm (very typical) and you have a JL DVC at 4 Ohm each, then wire it in series to achieve 8 ohms, and it will drop in. You can post up the actual numbers and I can give you a better explanation on what to do. (the short-
Series will "add the ohm ratings together". Parallel will "divide the ohm ratings in half"
Run from amp<--------RED Black------> Run to amp
Run from amp<------ Red ---Connect----Red
Run back to amp<---Black--Connect----Black

The not-so-short

As I'm sure you know, the quality and volume of a subwoofer isn't necessarily the size or quality of the sub, but is the correct matching of subwoofer and box size. This presents a problem. Many of JL audios subwoofers are renown for their quality, but mainly because they are specifically pared with boxes that are the right size for the subwoofer.

to optimize the quality of your subwoofer, your best bet will probably be to use a JL audio box, made for your speaker. If this is not an option, or if you want to do your custom work, then check online for the subwoofer specs, and what type of box it requires.

If Just by chance you luck out, and the subwoofer uses the same amount of backspace as your factory box, and the ported/not ported and sub box material are on par (see below), its near the same wattage with about the same stroke length, then yeah you should be able to drop it in (assuming it fits and the such above). Theres one big problem with this scenario however... Whats the point? You won't see much of a difference from the factory one!

If you choose to take this route, and you need a little more box cu/f, then you can still manage by taking some pillow or blanket stuffing, or "subwoofer" stuffing that has some flashy catchy name, and putting it inside the box. This allows it to "act" like a larger box. You may have to play around with the quanity a little bit to get the right sound quality and quantity.

Two big questions sit in my mind. Is the factory sub ported? Is the factory sub box merely sturdy plastic?

If it's ported or not will really affect the subwoofer your using. If anyone knows this information (I don't have the premium audio) then please post up, as that will help.

Secondly, the sub box. If it's merely sturdy plastic, then I'd be real hesitant to throw in a subwoofer with more power and a longer stroke, as it will either rattle, crack, or flex in a manner that will shorten the life of your subwoofer, and lower the sound quality substantially.

On the amplifier side of things. If the factory amplifier doesn't put out as much power as you want, then an easy fix is to get an amplifier with high inputs.

Note however, that this isn't necessarily the *best* way to do it, as ideally you'd fully rewire a better amp. However, it sounds as if your not interested in spending 2500 on a full new sound system, so this is a good low-cost option. Given that its an 8" and doesnt need that much power, this should be pretty easy and cheap. Put the subwoofer output from the factory amplifier to the high inputs of the new amplifier, and connect this amplifier to the subwoofer.

I tried to simplify this as much as I could. If you have any more questions, just ask. Your best bet may be to hold out for a Q-Logic or other brand factory mount box.

Hope that helps a little!

01 Jeep TJ
Plus 9 other less durable vehicles from Italy, Germany, and 'Merica
eighteenwheeler is offline  

Quick Reply

Register Now

In order to be able to post messages on the forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
Guy needs help replacing the CVT tranny on an '07 Compass Bluebell Jeep Compass & Patriot Forum 7 01-20-2010 07:58 PM
Possible subwoofer hidden for Compass? plunderisley Jeep Compass & Patriot Forum 8 09-11-2008 12:27 AM
Compass OEM Subwoofer/standard audio pkg davep Jeep Compass & Patriot Forum 7 04-02-2008 07:07 PM
Subwoofer enclosure 2007 Compass Limited :) rob_rector Jeep Compass & Patriot Forum 3 03-15-2008 06:15 PM
Subwoofer Installation Jason31 Jeep Compass & Patriot Forum 7 04-05-2007 08:53 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome