Bose Sub Woofer Replacement

[Ahsmo]

I figured I would start a thread to keep track of this process in case someone else wants to try this in the future. I am going to complete this project by Aug 12 so no teasing from me. This is an experiment so if it fails it fails.

 

I cannot stand the lack of bass. At neighborhood speeds the Bose system is almost adequate. At highway speeds it might as well be just a hollow plastic box under my center console. The most obvious solution is to put in a sub under my back seat and call it a day. Well my wife claimed that area as storage when we move. We move more than once a year it seems and down the road I would like to install something under that seat one day to hold rifles and shotguns securely.

 

The next obvious solution is to buy JL's stealth box that comes with a 10w1v2 and replaces the Bose sub woofer completely. That comes at a pretty hefty price tag of $575. The price is the biggest deterrence for JL stealth box. I'm sure it sounds good.

 

The last and final option is to replace the Bose woofer with another and add an amp. To me this seemed to be the cheapest/best-bang-for-my-buck option. So in the process of figuring out what would work well I acquired a spare Bose sub woofer system. I took the woofer out and measured the total internal volume of the Bose and then measured the volume of the port on the box.

 

This is what I came up with:

 

box internal volume: 7.405L(.261cuft)

port volume is .013cuft

 

I figured the internal box volume by weighting the box empty. Then I plugged up the port and filled the box with water. I weighed the box and figured out the weight of the water. With that I figured out the volume from the density of water at 70 degrees F.

 

The next step was to figure out the best replacement woofer. I used WinISD to model about 25 different drivers from different manufactures. I tried the box volume with the port plugged and the port open. After all of that, I settled on a 8" woofer from RE audio with the box sealed up. The next best choice was the JL 8w3. The RE audio driver offered nearly identical response to the JL woofer but at 1/4 the price. 6.5 inch drop in replacements did not model well at all in WinISD and after measuring and squinting my eyes I figured I could get an 8 inch woofer in that box without too much trouble.

 

The saga continues after I take the dogs to the vet ....

[Ahsmo]

Here is the spare box I have

[Ahsmo]

So this morning I pulled out my center console by following these instructions from the JL stealth box install instructions. This is where we are now:

[Ahsmo]

More pictures of the center console removed.

 

My next challenge is to figure out where to mount the amp I bought and how to run the power wire. I can't figure out where to mount the amp until the UPS man comes over. It will probably end up going somewhere up back behind the back seat.

[RayGMC]

I mounted mine on the back wall just off center towards the drivers side. I had to remove the rear seat to make enough room for installation. Make sure you position the location of the amp so the seat brackets don't touch it when the seat is put back in. I cut out a section of the sound deadening material on the back wall to make room for the amp. The section I cut out is the same dimensions as the amp. I didn't want to cut away too much and introduce more road noise. I carpeted the top and sides of a piece of plywood just a bit larger than the base of the amp and secured the amp to the plywood platform with screws. Then I used liquid nails to secure the back of the plywood(wood surface) to the back wall(metal surface) of the truck. I left the seats out over night and checked the sturdiness of the adhesive connection the next morning.

[Ahsmo]

I mounted mine on the back wall just off center towards the drivers side. I had to remove the rear seat to make enough room for installation. Make sure you position the location of the amp so the seat brackets don't touch it when the seat is put back in. I cut out a section of the sound deadening material on the back wall to make room for the amp. The section I cut out is the same dimensions as the amp. I didn't want to cut away too much and introduce more road noise. I carpeted the top and sides of a piece of plywood just a bit larger than the base of the amp and secured the amp to the plywood platform with screws. Then I used liquid nails to secure the back of the plywood(wood surface) to the back wall(metal surface) of the truck. I left the seats out over night and checked the sturdiness of the adhesive connection the next morning.

 

I will check that out once the guy shows up with the amp. How did you get the power wire through the firewall?

[RayGMC]

I ran mine from the battery down to the front passenger floor board. There is a plug that I drilled through and used a grommet to seal the gap. It was a lot easier than going through the firewall IMO.

[Ahsmo]

I ran mine from the battery down to the front passenger floor board. There is a plug that I drilled through and used a grommet to seal the gap. It was a lot easier than going through the firewall IMO.

 

I ended up doing exactly what you did with your amp. I am waiting for the glue to set up to double check that the amp is going to sit back there with the seat in.

 

I am going to look look around some more for a place to route wires once I confirm that amp position is going to work.

 

Here is where I am now: I pulled out the back seat.

[Ahsmo]

I cut out a piece of wood to mount the amp on. I am using t-nuts to secure the amp to the wood. Wood screws would have worked fine but I figured I would take the amp off the wood several times which would strip out the screw holes eventually. It is too hot outside for anything other than beer drinking.

[Ahsmo]

here is what the t-nuts look like.

[Ahsmo]

Before someone rips me for Boss audio amp, I'll explain:

 

The Boss Audio amp had a few things I was looking for: cheap, high level inputs, bass boost, and a remote sub woofer volume control and CHEAP. It is supposed to do 110w x 2 at 4 ohms(per chan). I really doubt that it can manage that but it should be able to manage 75w x2.

 

However, I was surprised how much the amp weights. The heat sink is a massive chunk of aluminum which for 70 bucks...I didn't expect that.

 

If it really does fail, I'll pick up a phoenix gold amp and call it a day.

[Ahsmo]

Okay I have the power wire run through the truck back to the amp. I have the amp turn on wire soldered in and ready to go. I ran the wires for the sub. I need to get some more speaker wire to run back to the amp for the high level inputs. I also need about 2 feet of power wire to finish things off as well. So my 10 dollar ebay amp kit was not enough. Go figure

 

I spent most of the morning fooling around trying to get the power wire through a grommet on the fire wall without tearing anything up. I ended up using the one on the driver's side up behind a fuse box/distribution panel.

 

I attached the remote turn on wire to the white wire on the harness that goes to the bose amp. At first I was stumped because it takes a minute or so for the truck to secure power to the white wire when you pull the keys out. I kept going in circles trying to figure out if my DVM had a good ground or not and if I was poking the lead into the right pin on the harness.

 

With the glue holding the wood panel to the back wall dry, I mounted the amp up and test fit the amp and the seat. I have about 1/4 inch of space with the seat folded up. Tomorrow I am going to finish the amp install and set the gain. My original plan of finishing tomorrow might have to get push back a bit to accommodate a wedding I am going to.

[Black02Silverado]

I just added a JL amp and sub to my 02 Silverado. JL is running a special now if you buy an amp they will give you a sub for free.

[icetraxx]

I've been debating doing this also. Since you have already done the math, what Re 8" sub did you end up going with if you don't mind me asking. I'm currently running a shallow mount pioneer 12 in a sealed box under the rear seat. I'm also debating just pulling out the bose sub and mounting my sub amp and a component am in place of it.

[Ahsmo]

I've been debating doing this also. Since you have already done the math, what Re 8" sub did you end up going with if you don't mind me asking. I'm currently running a shallow mount pioneer 12 in a sealed box under the rear seat. I'm also debating just pulling out the bose sub and mounting my sub amp and a component am in place of it.

 

Rex 8. $49 dollars on eBay. The 8w3 had a slightly better response curve than the Rex 8. Bose and gm left a ton of room on the table. There is plenty of room under there for amps without the Bose box there.

 

 

I am in Chicago for a wedding so progress has stopped until Monday. I did manage to cut up the Bose box and I cut a piece of wood out to hold the re sub. If I was to do this again I would buy a router circle jig and glass in a speaker ring. If I had done that I would have the box done already.