[Vyper340]

Would like to see the pics of the wiring and routing for the B&W system and sub install.

What units foot in the spare tire well?

[Tch-Nrd]

Originally Posted by DropTopKingM3

Like the title says, show me your aftermarket trunk subwoofer setup. I have a Bimmertech amp and Focal speakers on the way but I'm looking to add an additional sub to the trunk. I'm not looking to go too drastic as far as a JL audio W7 but I would like to feel my music a bit.


I'm looking at sub, box, amp all in one but I've never heard one of those setups in person.

I did the Bimmertech Amp and Alpha 1 speaker upgrade including under seat subs.
I still wanted more.
You can go JL W7 if you really want to.

I did!!!

Here is my install.
NVX sound deadening material under the trunk spare tire area. (I did remove my spare tire - I have roadside assistance)
Mounted the amp to a board and affixed the board to where the spare tire would go.
One rca cable from DSP to amp and one positive/negative run of speaker wire from amp to sub.
Power cable is just under 12" long due to battery being in the trunk.
Ground cable is just over 12" long due to ground post being next to the battery.
It was by far, the easiest install I've ever done and sounds better than any system/setup I've ever had. Plus with the bass knob up at the driver's seat you don't have to crank it to max level. I probably drive around with it between 40% - 60% and crank it up between 80% - 100% when my daughter rides with. She loves it!!
I forgot to take photos of the amp installed and wired, it's clean!
Also forgot to take photos of the entire trunk covered in sound deadening material. The one I included is about half covered.

[-cj-]

Does any company offer a pre-made “stealth box” for the X5? I wouldn’t mind throwing the sub in the spare tire well, and maybe the amp where the second (missing) battery goes. That seems to be the cleanest install IMO. How big of a sub have people fit in the spare tire well?

[racinghart03]

Looks great!! Glad to see some folks still like a little bass in their trunk! I have a 12" W7 with a HD1200 Monoblock. Good enough for me.

[-cj-]

Anyone know how much the rear trunk has changed between X5 models? I’d love a ghost enclosure that doesn’t take up any space..

Alternatively, does anyone know of one that fits in the spare tire well?

[Tch-Nrd]

Originally Posted by -cj-

Anyone know how much the rear trunk has changed between X5 models?

From this photo I took while installing my setup. It appears that ghost sub you pictured, won't work.

Our G05 have a positive battery terminal where that ghost sub goes...

[-cj-]

Originally Posted by racinghart03

Looks great!! Glad to see some folks still like a little bass in their trunk! I have a 12" W7 with a HD1200 Monoblock. Good enough for me.

That’s my exact setup. Can you post some pics?

Originally Posted by Tch-Nrd

Our G05 have a positive battery terminal where that ghost sub goes...

I finally took a peak and you’re right. Darn. Thanks!

By the way, my car does not have a spare tire. I’m thinking of anchoring some MDF or plywood down in the spare tire well to mount my amp. Does anyone know if I can secure to the mounting hole that the spare tire would mount to? And what size of bolt I need? I haven’t taken things apart yet to peak.

[-cj-]

Originally Posted by Tch-Nrd

Mounted the amp to a board and affixed the board to where the spare tire would go.

Power cable is just under 12" long due to battery being in the trunk.
Ground cable is just over 12" long due to ground post being next to the battery.

Sweet! This is essentially my setup as well. Mind telling me how you secured to the spare tire mount? What size bolt? I never had a spare tire, so maybe I’m missing some of the equipment.

Also, did you consider running your negative wire directly to the battery? I believe it was JL that did a study and recommended battery grounding vs chassis.

[Tch-Nrd]

Originally Posted by -cj-

Sweet! This is essentially my setup as well. Mind telling me how you secured to the spare tire mount? What size bolt? I never had a spare tire, so maybe I’m missing some of the equipment.

Also, did you consider running your negative wire directly to the battery? I believe it was JL that did a study and recommended battery grounding vs chassis.

I drilled a hole in a wood panel the size of the spare tire well, then used a bolt to tighten that down to the spare tire holder. I took out the spare tire hold-down all thread rod and took it to the hardware store to get a proper matching bolt. (8mm - 1.25x90mm)
As for the negative cable. There is a negative junction on the chassis, right next to the battery's negative terminal. I connected to that, it's similar to the positive terminal that's next to the battery. Here's a photo I took of that.

[-cj-]

Has anyone tapped into the positive OEM distribution box next to the main battery? I was thinking of attaching a 0/1 awg cable right off the same screw as the the battery plugs into. I ASSUME this distro block leads to the alternator and something else..

[-cj-]

Technic PNP harness arrived today and worked perfectly. Now I need to dial in the multiple gains on the LOC and the amplifier.

One strange thing: I got a TPMS malfunction 20 minutes into my drive. I read (briefly) that the system is located under the spare tire well? I wonder if my amp is somehow interfering with the system.. anyone else run into this?

Edit: reset the TPM and so far so good. Very weird.

I can’t believe how well sealed the X5 is. I don’t even have the double glazed windows and I wouldn’t be surprised if BMW removed some sound deadening from the X5M.. but it’s nearly silent outside the vehicle.

[Tch-Nrd]

Setup looks good!!
I tapped into that positive distribution block next to the battery. No issues.

[-cj-]

Just a slight update. My amp was causing interference with the TPMS and comfort access systems. I upgraded to the same amp, but newer, and my problem went away. The amp was a JL HD1200/1. I read about people on the internet having the same exact problem - I thought I had caused it, but turns out some amps emit a lot of RF noise(?).

[moose13533]

I wanted to post the sub I added to my X5. This forum has been very useful so I wanted to contribute.

I built a sealed enclosure for a single JL Audio 10w6v3-D4. I wanted the most HQ bass I could get in the smallest form factor. I also wanted a wedge shaped enclosure to matched the tilt of the rear seats.

I used a Focal 1.550 subwoofer amp, WavTech LinkDQ, and WavTech bass control. The Techniq PNP wiring harness made connecting into the factory subs super easy. I tested the running voltage at 14.8V so the amp is running at or slightly above full rated output.

The combination sounds super tight and clean and integrates into the factory Harmon Kardon system well. Turned up, there is a ton of output.

I have done many installs in my life, this was the easiest I have done given a rear battery. I mounted the bass control in the front compartment and ran the wire without removing door sills as the wire could be tucked. I did need to remove the back seat bottom to get the wire fully to the back. The power and signals wires were super easy to run on the left side. I used a free grounding post near the signal wires and an available bolt on the positive terminal. Taking the rear compartment cover off (2 bolts) and spare tire insert (10 plastic pins) was sufficient for full access to everything.

I used a Schoche 8G amp disconnect for power and a molex connector for signal wires so the sub is quickly removeable for cargo. Both of these came from Amazon.

The enclosure is MDF, glued, sealed, routed, and sanded. Then primed, filled, and sprayed with with a textured paint from HD. I used blind nuts and 4mm bolts to mount the driver. Blue loctite was used to make sure they don't work lose. I have rubber feet on the bottom of the sub and bolted a 3/16" eye hook to the sub. This is connected with paracord to the lower latch point to keep the sub in place.

[Jobio]

Originally Posted by Tch-Nrd

From this photo I took while installing my setup. It appears that ghost sub you pictured, won't work.

Our G05 have a positive battery terminal where that ghost sub goes...

Curious why you sound dampened the spare tire well. I’ll be doing an install similar to yours (amp in tire well + sub in cargo area), but didn’t consider needing this.

[Tch-Nrd]

Originally Posted by Jobio

Curious why you sound dampened the spare tire well. I’ll be doing an install similar to yours (amp in tire well + sub in cargo area), but didn’t consider needing this.

Honestly, I wasn't sure if it was going to echo, rattle or sound tinny. And I didn't want to pull it all out and install the material if it did. So I preemptively put it down. Not sure if it helped as I never tried before and after. I had also planned to do the entire rear hatch area and floor under the carpet. But after 5k mi and plenty of vibrations, there's absolutely no rattles. I'll likely sell the leftover to a friend of mine.

TL;DR The sound deadening is probably not needed.

[Dr. Jekyll]

Thought I'd add mine to your thread even though I had one up a few years ago.

[Jobio]

Decided to keep it straight forward for the first sub: a preloaded JL truck wedge with a 12TW3 mounted to the rear seats so that it goes down with them when they fold. A JL XDM 600/1 fit nicely in the small storage compartment with the factory components. A Match UP10 and Helix conductor controls everything. Shop did an amazing job fabricating the conductor holder out of carbon fiber so that it matches the rest of the carbon fiber in the interior of the car.

[mji111]

Super easy to do yourself with the technic harness. This prefab truck box fits nice and snug in the spare tire area. No loss of cargo space and very stealth. Bass knob fits nicely in the little change drawer on the left side of the dash. This is not going to win any bass contests, but is a night and day upgrade to the HK system. I had the Rockford powered sub in my old M4, but it was too big to fit in the spare area, so I went with this setup. Sounds basically the same as that. Both are/were 10”s.