UPDATE on 8" Shallow Mount Subwoofer drivers to fit in 01-02 OEM box

[YukonXL04]

Pull the cargo panel, pull the subwoofer, and get some measurements. From there you can find out what fits. Or search for what other subs people have put in and look up their dimensions, then buy a sub similar to that.

 

[Rocket Man]

The sub in mine is internal in the enclosure- the only thing I can see without tearing the enclosure open is a bass port and another different looking opening that looks similar to a bass port. I don't have time to tear it all apart and put it back together because my truck is needed for a relay race this weekend. And believe me, I've searched for any information from others who have replaced the sub itself but no luck. This is a picture of the enclosure someone is selling on EBay. I was hoping to find someone who has found a suitable replacement for just the sub. I'll probably just have to wait until next week and tear it apart all the way. I can't believe that with all the Bose systems out there somebody hasn't posted information on this Bose enclosure. I will do that when I figure it out. Thanks.

 

[YukonXL04]

Sorry, didn't realize the denali box was different. Might be better off grabbing a stock tahoe box and putting one of the known subs in it. Doubt that ported one would have enough airspace for a aftermarket sub

 

[Rocket Man]

I don't know why I didn't think of that. Thanks.

 

[Sub]

Red Rocket... yes, you've discovered that the 2000-2002 Denali and Denali XL rear subwoofers are Bose "Accoustimass" tuned subwoofer units... the driver inside those tuned ported boxes is more like 5.25". This is not the box into which you can add an 8" driver, even if you did have time to take the box apart.

Bose Accoustimass systems in vehicles are similar to their audio design concept in home theater systems. There is a very small driver inside that is sonically "amplified" by tuned porting... like a yell leader who holds a non powered megaphone to his mouth from the football field to yell cheers up to the stands of the game attendees.

The electrical Bose amplifier attached to the sub is not only for that specfic sub, it is also to support the "surround sound" effects that the luxury Y91 sound systems have. You also have a center channel pair of speakers mounted in the console of your Denali, as well as "twiddlers" (distinct from tweeters) in the back pillars of your Denali, that all work a little bit different than the non Denali sound systems.

Once you unravel one piece, you'll soon find you might need to unravel all of it.

This thread was intended to explore the options for NON Denali, NON Bose Luxury, long wheel based Suburban / YXL factory enclosures. I suppose because there are more short wheel base Tahoes and Yukons on this forum, the discussion naturally gets pulled toward that application instead. And that's OK.

But to put an aftermarket 8" or 10" sub in your Denali, you will have to either obtain a Tahoe box, make a box, or get the MTX box. You will also need an amplifier, because the base portion of the Bose amplifier is only good for 100 watts. That isn't a guess, by the way. That is from the specifications for that particular Bose amplifier.

 

[Rocket Man]

Hmmm. As a whole, the system rocks in all honesty. I did a DD mod and installed a Sony XAV0602BT (Bluetooth) with back-up cam and a PAC steering wheel control interface. That seemed to wake things up. I just want a bit more bass. I think I'll go with the MTX box and I'll get a good 2-ohm sub for it and wire it to the stock amp. Then if it isn't loud enough I can get a good 2-ohm stable amp. I don't think I'll have to do anything to the rest of the system. My HU has a sub preamp output if I go with the aftermarket amp. The Sony also has something they call "rear bass enhancer" with 4 settings for when the sub pre outs aren't used and it works pretty nice too. Like I said, the system sounds real good, just needs a bit more bass. Sorry, I realize my situation is different from what your intended audience is, but if it pulled me in I'm sure it will others with similar situations who will benefit. Thank you. Your insight into the Acoustimass system is invaluable.

 

[Sub]

I think Jeff's install that I reposted for you in this thread is about the most instructive and similar to your situation as you will find on TYF. You will notice that his "before" pic that I reposted shows the same Bose Accoustimass subwoofer box that you found a photo of on eBay. Same unit. Compare his pic with yours.

Anyway, if he did it, and was happy with it, then it sounds like you will be pleased with a similar installation. The advantage you have with the short wheel base and the MTX box is that you have a ready made solution for a 10" sub, rather than an 8". All things otherwise being equal as far as quality of components and design, the larger subwoofer driver is generally capable of reproducing lower frequencies at louder volumes than a smaller subwoofer.

If I were in your shoes with your vehicle, and wanted the MTX box, I'd strongly consider getting the version with the built in amplifier... especially since your aftermarket head unit already has a dedicated subwoofer out. The built in amp would save so much headache in the installation, finding a board for the amp, carpeting the board for the amp, sizing the amp for the driver, sizing the amp for the folded seat clearance, running wires under the seat but making sure they don't get pinched, stepped on, or shorted through the seat mechanisms or by kids and their sports apparati... the list goes on.

I don't work for any audio company, and never heard of MTX prior to my research into subs, but there is no way I'd pass up the opportunity to have all those issues solved for me inside one ready made, pre tested box.

 

[treehan77]

I would argue to NOT get the amplified option. I would prefer just the enclosure. This would allow easy, cheap, flexible replacement options in the future if the sub or amp stops working.

I think Jeff's install that I reposted for you in this thread is about the most instructive and similar to your situation as you will find on TYF. You will notice that his "before" pic that I reposted shows the same Bose Accoustimass subwoofer box that you found a photo of on eBay. Same unit. Compare his pic with yours.

Anyway, if he did it, and was happy with it, then it sounds like you will be pleased with a similar installation. The advantage you have with the short wheel base and the MTX box is that you have a ready made solution for a 10" sub, rather than an 8". All things otherwise being equal as far as quality of components and design, the larger subwoofer driver is generally capable of reproducing lower frequencies at louder volumes than a smaller subwoofer.

If I were in your shoes with your vehicle, and wanted the MTX box, I'd strongly consider getting the version with the built in amplifier... especially since your aftermarket head unit already has a dedicated subwoofer out. The built in amp would save so much headache in the installation, finding a board for the amp, carpeting the board for the amp, sizing the amp for the driver, sizing the amp for the folded seat clearance, running wires under the seat but making sure they don't get pinched, stepped on, or shorted through the seat mechanisms or by kids and their sports apparati... the list goes on.

I don't work for any audio company, and never heard of MTX prior to my research into subs, but there is no way I'd pass up the opportunity to have all those issues solved for me inside one ready made, pre tested box.

 

[Rocket Man]

I just ordered the MTX Thunderform box unloaded. I've never cared for MTX subs and instead of giving them $200 for theirs I got a JL 10W1V3-4 (4 ohm) for $150. I love JL subs and it's rated for slightly less than the volume of the box, mounting depth is compatible and excursion should be fine at .45". If it hits I can space the bottom of the panel out like Jeff did. I also decided to go ahead and get an amp for the sub and decided on the Soundstream Picasso Nano Monoblock PN1.450D, rated at 260 watts RMS at 4 ohms. It's small at 4.75" x 8" x 1.5" and I have a Picasso Nano in my Harley and it sounds great. It comes with a remote-mounted controller for adjustments. I picked it up for $90 and it will be a lot better than the 100 watt RMS one that MTX offered for $100. I'm sure I can find a place for it and the JL looks like it should be happy with around 200 watts RMS optimal so hopefully this should all work out great. I didn't want to spend this much money but after considering my options I didn't have much choice. The Bose enclosure wasn't upgradeable and choosing between a stock Tahoe enclosure and the MTX Thunderform was easy.

 

[treehan77]

Anybody have a later model like mine (2005) that has the sub area not cut out? Does the mtx thunder form come with a template to cut out for the speaker or what?

 

[Rocket Man]

If you go to their website and look at the enclosure there's an install file pdf under support files. It shows them cutting out for the grill which looks to be included. It says there's a template. What's not clear is if they're talking about just modifying the existing speaker hole in the cover or what. I assume you're talking about cutting the plastic cover panel? I would suggest getting ahold of MTX for clarification.

 

[YukonXL04]

If you go to their website and look at the enclosure there's an install file pdf under support files. It shows them cutting out for the grill which looks to be included. It says there's a template. What's not clear is if they're talking about just modifying the existing speaker hole in the cover or what. I assume you're talking about cutting the plastic cover panel? I would suggest getting ahold of MTX for clarification.

According to the MTX install guide there is a included grill and template for it. you can also take a dremel and cut out each individual hole on the factory grill. Either or. Also you could take a factory cargo panel from a 99-02 that has the holes already cut into it and just swap panels. 3 different options for you.

 

[treehan77]

huh cool, hopefully i can find one of these mtx enclosures cheap, they want a pretty penny...or i'll have to build one

 

[Rocket Man]

I got my enclosure today and the included grill is definitely meant for the factory cutout- it's a beveled piece that fits where the factory cutout is countersunk. I'd suggest either mounting a regular grill or finding a stock panel that has the sub cutout. I can provide a picture if needed.

 

[TheAutumnWind]

On my 03 Tahoe, I was able to find a factory rear sub box at of a 01 Tahoe and mounted it in the rear cargo area just like it was factory from 00-02. I did a JBL 8" swallow mount as well. So not only do I have the factory sub in the center console on my 03, but a bit extra "Thump" coming from the rear.

I like this idea.

 

[Kain452004]

For anyone interested, I bought this sub for my 01 Tahoe and it fit perfectly in the factory box.. Only had to drill new holes...


Kicker 40CWS82

 

[crazycrew]

Hmmm. Any certain tahoe or yukon I should look for to get this factory box out of?? I have a loaded LT, but from the looks of the panel (no holes cut out), It doesn't appear to have the oem subwoofer. 2004 Tahoe

 

[treehan77]

Hmmm. Any certain tahoe or yukon I should look for to get this factory box out of?? I have a loaded LT, but from the looks of the panel (no holes cut out), It doesn't appear to have the oem subwoofer. 2004 Tahoe

01-02 like the post title says

 

[crazycrew]

Ok, wasn't sure if it were just those

Sent from my SAMSUNG-SM-N910A using Tapatalk

 

[ge0rgin0]

Do you mean the Denali XL?

Or do you mean the Denali short wheel base?

The MTX Thunderform doesen't fit the Denali XL because it is a long wheel base, and the factory space for the rear mounted hidden subwoofer is constrained by the cubby hole directly above the sub. Since this cubby hole is formed into the factory rear quarter panel plastic trim, it is impossible to look stealth, or look factory, but cutting the entire quarter panel out. MTX never offered a Thunderform for the Denali XL, Yukon XL, Suburban, nor the Cadillac ESV.

The MTX Thunderform DOES fit the short wheelbase Denali, even though you may have read that it doesn't. The unit actually does, but to install it requires moving the Denali amp that is in the way.

The factory BOSE amplifier is the key difference between the Tahoe / Yukon short wheel base, versus the Denali / Escalade short wheel base. In the Tahoe and Yukon, the amplifier is located up front behind the glove box in the 2000-2002 models. However, in the Denali / Escalade of the same '00-'02 years of the GMT800 body style, the luxury amplifier is larger, and is located in the rear of the vehicle, on top of the factory Bose sub..

The fact that this Denali amp needs to be relocated to fit the MTX Thunderform is most likely the reason why you may have read that it doesn't work in the Denali.

However, remember that cubby hole I mentioned earlier? The cubby in the Suburban and Denali XL that is directly on top of the factory sub in the long wheel base vehicles? The cubby hole that gets in the way of installing an enclosure with enough internal volume to support a 10" driver?

Well, in the short wheel base Denali, as well as the Tahoe and Yukon, the factory cubby hole is more forward over the rear wheel well, instead of on top of the factory subwoofer, where the amp in the Denali is. Therfore, if you take the rear factory amp in the Denali that is on top of the sub, and move it INSIDE the cubby hole that is on top of the wheel well, then the MTX Thunderform will fit perfectly in the Denali.

When you move the amp forward, just swivel it around 180 degrees, so that the plugs into the amp essentially stay in the same general location. Fortunately, the Bose amp electrical connectors are all on only one side of the amp, not two. So by pivoting the amp around 180 degrees, no extensions of any wire harness is needed.

A TYF member named Jeff did exactly this. His user name is JustPlayInn. Here are some photos he took of his installion of an MTX Thunderform into his short wheel base Denali:

BEFORE, with Factory Bose Sub, and Factory Bose Y91 LUXURY Amp on top:

View attachment 166024

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BARE, after factory sub and amp and bracket all removed. NOTICE the GM OEM "Dynamat Extreme" installed at the factory directly behind where the subwoofer mounts (on the gas filling port bump in of the sheet metal):

View attachment 166025

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BOOM, with the MTX Thunderform 10" hidden blast box in place, fitting perfectly in the Denali short wheel base (Jeff installed a Polk Audio driver instead of going with the MTX driver)... only the factory amp is MIA:

View attachment 166026



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BAM, with the Bose factory amplifier cleverly swung around 180 degrees so as to maintain the factory wiring harness lengths, with a connector port hole drilled in the aft end of the cubby hole, and the stock amp fitted perfectly in place:

View attachment 166027



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BONE stock look after the job is complete:


View attachment 166028


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Photo credit: All photos from "JustPlayInn" (Jeff), and this was his installation as well.



Like I said in a previous post, if I had a short wheel base, Denali or otherwise, I'd be inclined to go with the MTX Thunderform. You can get it as a bare box and put in your own driver, or as a loaded box, with the MTX driver, or as a full package deal with the box, the driver, and the amp for the sub built in. This latter fully packaged version is what I would do personally, because there is a lot of value in a pre engineered solution. Having to find a place to hide yet another amplifier is something I'd rather avoid, so why not get one built into the box itself?

Sick Install ..still have it?