Crypto69

Hi folks, I wanted to share a custom sub install I recently had done in my 2013 S8 that I am really happy with. Like a lot of people with S8/A8, even though I have the top of the line B&O system, I was shocked at the lack of bass in an otherwise fine sound system. I’m providing this write up to help any other audiophiles who might not be happy with their stock system.


2013 S8 with 22" Blaque Diamond Wheels

I’m an audiophile who considers a good sounding system a vital part of a car and the bass was just not cutting it. In fact, I blew the factory sub in about a week or two simply trying to get more out of it. I can’t say I was really upset about it - it just gave me the opportunity (excuse?) to upgrade the B&O’s achilles heel. I took my car to a local car audio shop I trusted called Cartronics in Brentwood, TN - they did a complete overhaul of all factory speakers and amps in my 2007 S65 AMG. I had everything replaced with Focal and Audison components and it sounded great. Now I had a new car - it was time to start over.

I started looking around for replacement options. At first I thought I could simply drop a new 10” in to replace the blown factory sub and add an amp to make it stronger. Seemed like a reasonable upgrade. I wasn’t really sure it would give me enough bass but it wasn’t going to be that expensive so I gave it a shot. Long story short, it didn’t not work out well. The replacement Hertz sub they installed also blew as soon as I got back into my car after the install!

Disappointed, I started looking for a plan B. The obvious option was simply to drop a dual sub box in the trunk behind the back seats. I really was not keen on taking up almost half my trunk with a sub box as well as ruining the stock appearance. An additional concern was the vents on the back seat that are exposed in the trunk that help cool the factory amp and other electronics that are behind that panel. Restricting the air flow could lead to problems down the road.

Looking around on YouTube, I came across this video showing a complete overhaul of a 2012 A8 including all Bose factory speakers and sub.

I took 2 things away from this video that I liked:

1. Using the rear wheel well to add a new 12” sub without taking up much space in the trunk and preserving (most) of the stock appearance.
2. The gain control **** in the front cup holders.

After talking with Cartronics about installing something similar in my car, we settled on installing a single 13.5 JL TW5 in the passenger side wheel well (if it would fit). The TW5 is a shallow depth sub that hits hard - really amazing for a sub of its size and volume requirements. Turns out after they did some measurements, the 13.5” was just too big for the space. I was going to have to settle for a 12” in that space - or so I thought.

Cartronics pitched me one more idea before we moved forward - how about installing 2 10” subs in both wheel wells? 50% more bass for not a whole lot more $? Yeah, lets do it!

So, here is what they installed:

• 2x10” JL TW3 subwoofers
• 1 Rockford Fosgate T500X1BR amplifier

The TW3 is one step below the TW5 but shares a similar design and provides great performance. The Rockford amp is rated 500 watts but like most Rockford amps, is underrated and actually puts out about 700w. The amp is tiny too! It fits nicely under a little shelf under the factory amp. Perfect fit!


Space for Rockford Amp


Back seat panel removed

The fiberglass sub boxes were custom molded and fabricated to fit the rear wheel wells on both sides. They did an amazing job matching the factory carpet and providing an exact fit. Nothing on the car was cut or modified to install these subs. It could all be removed and restored to stock without any residual traces if necessary. Here are some pictures of the fiberglass box fabrication:


Box for left wheel well


Nice Shop Poster (oh, and Box for right wheel well)






Wheel wells ready for custom boxes:




JL TW3 Ready for Install

Adding a gain control **** is a GREAT way to customize bass on the fly for each album or even song you are playing. Its simply control for your bass output that is as easy to use as a normal volume control. There are literally no remaining blank factory cut-outs to install this new **** so, again inspired by the original YouTube video above, they used the cigarette lighter spot to install the gain control ****. Unlike the video, however, they installed an actual high quality rotary **** which replaced the factory lighter.




Here are some pictures of the finished product:





So, how does it sound? Subjectively, It sounds amazing. I've got all the bass I need and more and I didn't make any permanent changes to my car. It hits hard. I listen to metal and rock and it reproduces even blast beats and kick drums accurately and with punch. No mud or mess - just clean punchy bass. I could not be happier. All in all, the cost was about $3,500 for parts and installation. Well worth it to me to complete the car and add much needed bass to my sound system. Cheers.

Doctormario

Crypto69

Thank you for the kind words. I am not sure why "k-n-o-b" is censored in the post but it is indeed a really nice feature to have. I've always liked to tweak bass in my home media room using the gain k-n-o-b on my sub depending on the movie content and this allows me to do the same in my car for music.

rally

Crypto69

Thanks. If you (or anyone else for that matter who wants to take a look and listen) find yourself in the Nashville TN area, just let me know and I'd be happy to arrange a meet up.

TinyElviss

The gain k-n-o-b placement is positively brilliant! Will the cup holder cover still close?

Crypto69

Yes, in fact it will. When Cartronics first sent me some update photos, I was concerned about the same thing because it looked too tall for the door to close but it does. I generally keep it open anyway so that would have not been a show stopper for me.

Kelzo

Love this post and just cost me $3.5k
I have had my 15' S8 with the B&O package for about a month. The sound is truly amazing on about 70-80%, like unreal! however, when I want the system to bump, it's not designed for that and is lackluster unfortunately.
This setup is perfect, looks almost original and I bet it sounds truly phenomenal with the other B&O speakers etc?

Crypto69

Yeah, the bass in the B&O system is really the only thing holding it back. The rest of the system is really top notch and when you add this new level of bass, it really brings out the rest of the system. I was always distracted by the lack of bass in the system, focused on that, instead of appreciating what it did well and that is the mids and, most of all, the highs. The tweeters in the B&O system are amazing. I had a MB S65 AMG with a Focal/Audison install and this B&O system, with the bump in bass, really comes close to matching it. The B&O tweeters are just a half-step below the Focals but would certainly not be worth "upgrading". I am very happy with the performance of this system.

polo1

I wonder if one of these would do the trick...

https://www.crutchfield.com/p_109BAS...ssPro-Hub.html

Or two of these - one in each of the trunk corners where you put the 10" custom ones in - they would probably fit and you could use the stock carpet covers to hide them...

https://www.crutchfield.com/p_109BAS...Pro-Micro.html

Or one, or two, of these...

https://www.crutchfield.com/p_108BAS...ssLink-DC.html