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Raxiom by JL Audio Subwoofer Upgrade Kit (15-20 Fastback w/ Factory Subwoofer)

Item 393867
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      Video Review & Installation

      Hey, everybody, I'm Justin with, and in this video, I'm gonna be taking a closer look at the Raxiom by JL Subwoofer Upgrade Kit for all 2015 and newer Fastback Mustangs, equipped with a factory subwoofer. Now, in my detailed breakdown, I plan on talking about why prospective buyers might wanna upgrade their factory sub in their Mustang with a 12-inch option here from JL. We'll talk about what's included with the kit along with some of the specs, and then finally, we'll cover a brief, little overview of the installation process. I'm gonna go solid two out of three wrenches here on the difficulty meter due to the light wiring of course, but we will have some more detail on that later on.Now, the JL kit that we have in this video, again, will appeal to those 2015 and newer Fastback owners who have the Shaker Pro Audio System with the 12 speakers in the factory subwoofer, but feel like the factory sub just tends to fall a little short in regards to overall output or quality. Now, by going with this turnkey system here from JL, you're gonna be replacing that 8-inch factory subwoofer and the 100 watt factory amplifier with one of JL's 12-inch subwoofers and corresponding 500 watt amps. So, in turn, you're gonna be getting a much bigger bass response overall, a lower frequency range, and just a lot more thump, while still essentially maintaining the same amount of usable space in the trunk. And with all that said, I do feel like the biggest appeal with this kit here from Raxiom and JL is the fact that it is a turnkey system, essentially ready to rock and roll right out of the box.Now, could you piece together a different system using different components maybe save a couple of bucks? Sure, but this is a convenience factor, guys, you're getting everything you need from soup to nuts right out of the package. Yes, you gonna be spending a little bit more money for that, but you are getting quality components in return, and again, this thing is ready to install the moment you unbox it. So, Ford has been using their patented Shaker system for pretty much as long as I can remember, and for the most part those higher end Shaker offerings do produce enough sound and enough bass response to satisfy most owners. However, like anything in the aftermarket, some people just aren't satisfied with that and are looking for ways to improve with what the factory gave them. And that's pretty much what this kit will appeal to.Now, I can personally attest those factory Ford subwoofers do leave a lot to be desired, especially if you like a more bass heavy listening style. Now, the problem is outfitting or upgrading the subwoofers without totally dominating the trunk space like those old bandpass boxes back in the day, but still at the same time providing you with enough low end response or bass to round out the other 11 speakers in the 401A Shaker Pro package. So, Raxiom JL, they put their heads together, came up with a solution for that problem and that's what we're looking at here today. But, let's break down the individual components here of the upgrade kit from JL and Raxiom, and the star of this kit, at least in my opinion, is no doubt gonna be the JL 12 TW3 subwoofer, which is just a massive upgrade over that 8-inch factory paper cone woofer in every single way.Now, what makes the TW3 really special is that it produces a fantastic bass response, but it's still very shallow or very thin. In fact, this speaker itself is only 3.5 inches deep. So, that makes it very appealing to throw in tight spot like this because, as you can see, it really doesn't need a massive enclosure to sound really good. So, how did JL accomplish this with their TW3 line up? Well, they basically took a traditional woofer and just turned it inside out. And what I mean by that is, if you can envision a speaker, if you ever seen one outside of an enclosure, you know you have the cone and then the skeleton or frame, then hanging off the back of the speaker

      Product Information

      Features, Description, Reviews, Q&A, Specs & Installation


      • Raxiom Subwoofer Upgrade Kit by JL Audio
      • Delivers Deep, Powerful Bass
      • 12TW3-D4 Stealthbox Subwoofer
      • JL Audio JX500/1D Class D Amplifier
      • All Cables and Connectors are Included for a Hassle Free Install
      • Fits 2015-2020 Fastback Mustangs Equipped with the Optional Factory Subwoofer


      Raxiom by JL Audio. The optional eight-inch subwoofer that Ford offers for the S550 Mustang is okay, for a factory part, but it could sound so much better. That is why Raxiom turned to JL Audio to help them create a much needed upgrade/replacement kit. Working closely together, Raxiom and JL Audio hand picked the correct components to replace your Mustang's subwoofer to really bring your stereo system to life. By utilizing a Stealthbox Subwoofer and a Class D Subwoofer Amplifier this Upgrade Kit will deliver deep, powerful bass that will easily rival other high end sound systems.

      Stealthbox Subwoofer. Raxiom's Factory Subwoofer Upgrade Kit includes JL Audio's 12TW3-D4 Stealthbox Subwoofer. The Stealthbox Subwoofer is a direct fit replacement upgrade for your optional factory installed trunk mounted Subwoofer. The Stealthbox features an all-fiberglass, sealed enclosure design that is equipped with JL Audio's revolutionary 12TW3 thin-line subwoofer.

      JX500/1D Amplifier. To boost the power of the Stealthbox Subwoofer Raxiom chose JL Audio's JX500/1D Amplifier. This Amplifier employs a highly-efficient Class D design with a MOSFET power supply to deliver a strong 500 watts. Featuring a variable bass boost at 45 Hz with up to 12 dB of boost, this JL Audio Amplifier is configured as a low-pass filter with continuously variable cutoff frequency selection from 50-200 Hz. Dedicated hi-level inputs are included, in addition to conventional low-level RCA inputs. These inputs make it super easy to install the JX500/1D Amplifier to your original factory head unit.

      Application. This Raxiom by JL Audio Subwoofer Upgrade Kit is designed to fit 2015 to 2020 Fastback Mustangs that are equipped with the optional factory subwoofer only. Does not fit convertible models.


      Fitment: 2015 2016 2017 2018 2019 2020 Details

      Raxiom 393867

      CA Residents: WARNING: Cancer and Reproductive Harm -

      Installation & What's in the Box

      Installation Info

      What's in the Box

      • (1) Class D Subwoofer Amplifier
      • (1) Stealthbox Subwoofer
      • (1) Remote Bass Control
      • XD-MFB-MAXI Fuse Holder with Genuine 30A Maxi® Fuse
      • 17 ft (5.18 m) Red 30A Core Power Wire, terminated with ring
      • 3 ft (0.91 m) Black 30A Core Ground Wire, terminated with ring
      • 17 ft (5.18 m) Blue Remote Turn-On Lead Wire
      • 25 ft (7.62 m) Blue Speaker Cable
      • XD-CLRAIC2-18 2-channel, 18 ft. (5.5 m) Audio Interconnect Cable
      • Self-Tapping Ground Screw
      • Rubber Firewall Grommet
      • Nylon Wire Ties
      • Hex Wrench for Fuse Holder

      Customer Reviews (6)

        Reviews of Raxiom Interior products have an average rating of 4.0 out of 5

          Questions & Answers

          10 More Questions

          Will It Fit My Mustang

          • Bullitt - 19, 20
          • EcoBoost - 15, 16, 17, 18, 19, 20
          • GT - 15, 16, 17, 18, 19, 20
          • GT350 - 15, 16, 17, 18, 19, 20
          • GT350R - 15, 16, 17, 18, 19, 20
          • GT500 - 20
          • V6 - 15, 16, 17

          Fits Fastback Mustangs that are equipped with the optional factory subwoofer only. Does not fit convertible models.

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