If you’re a motorcycle enthusiast, you know that having a great audio system can really enhance your riding experience. That’s why we’re excited to introduce you to the Rockford Fosgate HD14-SBSUB, a high-performance subwoofer kit specifically designed for Harley Davidson bikes. In this review, we’ll cover everything you need to know about this impressive audio upgrade.

Table of Contents
Features and Specifications
Now let’s dive into the technical details of the Rockford Fosgate HD14-SBSUB. Here are some of the key features and specifications:
- Dual 10-inch woofers: This subwoofer kit includes two high-output 10-inch woofers that deliver impressive bass and clarity.
- High-output amplifier: The included amplifier is a Class D, 800-watt unit that can power the subwoofers with ease.
- Easy-access control panel: The control panel is located on the top of the amplifier and features easy-to-use dials for gain, crossover, and phase control.
- Durable construction: The subwoofer enclosure is constructed of weather-resistant materials that can withstand the elements.
- 1-year warranty: The Rockford Fosgate HD14-SBSUB comes with a 1-year warranty for your peace of mind.

M5-800X4 800-Watt 4-Channel IPX6 Amplifier
The Rockford Fosgate HD14-SBSUB package comes with the M5-800X4 800-Watt 4-Channel IPX6 Amplifier. This amplifier is specifically designed to power the HD14-SBSUB subwoofer, but it can also power other speakers and components in your motorcycle audio system.
Here are some of the key features and specifications of the M5-800X4 amplifier:
- 100 watts RMS CTA-2006 x 4 at 2 or 4 ohms
- bridged power: 200 watts RMS CTA-2006 x 2 at 4 ohms
- max Dynamic Power rating: 200 watts x 4 at 2 ohms
- Class AB topology for efficient power delivery and low distortion
- Variable high-pass and low-pass filters for customizing the frequency response of your speakers
- IPX6-rated for water and dust resistance, making it ideal for use on motorcycles and other outdoor vehicles
- Compact size for easy installation in tight spaces
- Includes all necessary mounting hardware and wiring harness for installation with the HD14-SBSUB subwoofer
In terms of installation, the M5-800X4 amplifier is designed to be mounted in a secure, dry location on your motorcycle. The amplifier’s compact size makes it easy to fit in tight spaces, such as under a seat or in a saddlebag.
To connect the amplifier to your audio system, you will need to use the included wiring harnesses and RCA cables. The wiring harnesses provide power and signal connections to the amplifier, while the RCA cables connect the amplifier to your head unit or other source component. (Remember The HD14-SBSUB Kit Comes with a quick plugin-style harness).
Once the amplifier is installed and connected, you can adjust the high-pass and low-pass filters to customize the frequency response of your speakers. This allows you to fine-tune the sound of your system to your preferences and the acoustics of your motorcycle.
Overall, the M5-800X4 800-Watt 4-Channel IPX6 Amplifier is a powerful and versatile amplifier that is specifically designed for use on motorcycles. Its compact size, water-resistant construction, and customizable filters make it an excellent choice for powering the HD14-SBSUB subwoofer and other components in your motorcycle audio system.
Tuning The Rockford Fosgate HD14-SBSUB
This system comes with tuning instructions for the amplifier. You won’t have to use your ears or learn about each setting. All you have to do is flick a couple of switches and turn a couple of dials. Because this add-on subwoofer kit was already tuned for the best audio output possible by the good folks at Rockford Fosgate all we have to do is switch it to their settings.
Here is a picture of the included amp tuning guide. I will paraphrase these settings so that they are easier to read below:

- The rear input level and front input level settings are both set to 02:00, which matches the amplifier input to the radio’s output and tells the amp where to “clip.”
- The punch EQ setting is set to MIN and is used to compensate for acoustical deficiencies in automotive interiors. However, it is not used on motorcycles.
- The input switch is set to 2CH, which means that only two inputs are required to feed all four amplifier channels.
- The crossover frequency is set to 80Hz, which is the frequency at which the crossover cuts off. It is set to allow only low frequencies to pass to the subwoofers and works with the HP/AP/LP switch.
- The crossover switch is set to LP, which allows the crossover to work in high-pass, low-pass, or all-pass (bypass) mode. It is also set to allow only low frequencies to pass to the subwoofers and works with the crossover frequency dial.
- Lastly, the preset switch is set to OFF and is only used for Motorsport (SXS) setups. It is not used on motorcycles. Overall, these settings are designed to provide optimal sound quality and compensate for any acoustical deficiencies in the environment.
Rockford Fosgate 10” M1 Subwoofer
The Rockford Fosgate HD14-SBSUB package includes two 10” M1 subwoofers with enclosures. These subwoofers are designed to deliver deep, powerful bass that will enhance your motorcycle audio experience.
The M1 subwoofers feature a high-excursion, glass fiber-reinforced paper cone that is both lightweight and rigid, allowing for a fast and accurate response to bass notes. They also include a rubber surround that helps to maintain a consistent and linear movement of the cone, reducing distortion and improving overall sound quality.
The subwoofer enclosures are constructed from high-density polyethylene (HDPE) that is both lightweight and durable. The enclosures are designed to be weather-resistant and feature a textured finish that is resistant to scratches and scuffs. They are also designed to be easy to install, with a quick-release mechanism that allows you to easily remove the subwoofers for maintenance or replacement.
Together, the M1 subwoofers and enclosures deliver a powerful, high-quality bass experience that is perfect for motorcycle enthusiasts who want to take their audio system to the next level.

Caution:
PROBLEM: The factory radios on Harley-Davidson® audio systems produced in 2014 and later are equipped with a high-fidelity EQ curve that can cause excessive distortion and lead to speaker damage when an amplified audio upgrade is installed.
SOLUTION: To fix this issue, Authorized Rockford Fosgate Motorcycle Dealers can perform a “flash” on your factory radio to remove the EQ curve.
WHAT TO DO: Visit the Rockford Fosgate website at www.rockfordfosgate.com/dealerlocator to find the nearest Authorized Rockford Fosgate Motorcycle Dealer who can perform the software update on your radio. Note that factory Harley-Davidson® techs are no longer authorized to do this software update. If you need more information, you can contact Rockford Fosgate tech support at 1-800-669-9899.
Compatibility
Before we get into the nitty-gritty of the Rockford Fosgate HD14-SBSUB, let’s talk about compatibility. This subwoofer kit is designed as an add on kit to fit Harley Davidson touring bikes from 2014 to current models, including the Electra Glide, Road Glide, Road King, and Street Glide already fitted with a stage 2 or 3 Rockford audio Kit. It’s a plug-and-play system that can be installed in just a few hours with basic tools. However, if you’re not comfortable working with electrical systems, we recommend having a professional install it for you.
For this system to work, you’ll need an existing rockford fosgate system. This is because the HD14-SBSUB is built to take signal input from the existing amplifier. Here are a couple of lists that will help you decide if this system works for you or if you’ll need to purchase something additional to make the kit work.
Required Audio System

Compatible Harley-Davidson® Motorcycles

How To – Installation of The Rockford Fosgate HD14-SBSUB
- Determine the compatible Harley Davidson models – The HD14-SBSUB is designed to fit 2014 and up Harley Davidson Street Glide, Road Glide, and Electra Glide models.
- Gather the tools needed for installation – You will need a socket wrench set, wire cutters, wire strippers, a crimping tool, electrical tape, and zip ties.
- Disconnect the negative battery terminal – This is a safety measure to prevent any electrical shocks or short circuits during the installation process.
- Remove the stock fairing – You need to remove the fairing to access the stock speakers and wiring harness.
- Disconnect the stock speakers – Remove the connectors from the stock speakers and set them aside.
- Install the HD14-SBSUB – Mount the HD14-SBSUB in the fairing and connect the wiring harness to the unit. Use zip ties to secure the wiring harness and ensure that it is not in the way of any moving parts.
- Connect the HD14-SBSUB to the audio system – Connect the wiring harness of the HD14-SBSUB to the wiring harness of the Harley Davidson audio system. Follow the color-coded wires to ensure that the connections are correct.
- Reinstall the fairing – Carefully reinstall the fairing and make sure that all the connections are secure.
- Reconnect the negative battery terminal – Reconnect the negative battery terminal and turn on the ignition to test the HD14-SBSUB.
- Adjust the settings – Use the equalizer settings on your Harley Davidson audio system to adjust the bass and volume levels of the HD14-SBSUB to your preference.
Tips and Tricks for Installation
If you’re planning on installing the Rockford Fosgate HD14-SBSUB yourself, here are some tips and tricks to make the process smoother:
- Use a torque wrench to ensure all bolts are tightened to the proper specifications.
- Disconnect the negative battery cable before beginning any electrical work.
- Use dielectric grease on all electrical connections to prevent corrosion.
- Test the system before reassembling the bike to ensure everything is working properly.
Tools Needed for Installation
Here are the tools you’ll need to install the Rockford Fosgate HD14-SBSUB:
What’s Included in the Box
Here’s what you’ll find in the Rockford Fosgate HD14-SBSUB box:
- 2 M1D2-10B subwoofers
- 2 subwoofer enclosures
- 1 M5-800X4 amplifier
- 1 wiring kit
- 2 cutting templates
- 1 amp mounting plate
- 1 1130-75394-C1 AP Pack containing the following:
- 12 Nylon zip ties (8 inches)
- 8 Phillips screws (M3 x 0.5 x 12 mm)
- 1 hole saw with an outer diameter of 45 mm
- 4 washers (outer diameter of 9 mm, inner diameter of 3.2 mm, and thickness of 0.8 mm)
- 4 hex screws with a 3/16 inch diameter, 5/16-18 thread, and 1.25 inch length
- 4 clips with a 5/16-18 thread
- 2 screws (M3 x 0.5, 5 mm)
- 8 thread cutting screws with ST3.0 thread and 6 mm length
- 2 nylon plugs with a 0.75 inch inner diameter
- 2 hex nuts (M3 x 0.5)
- 8 Phillips screws (#8 x 0.75 in.)
- 1 hex wrench with a 3/16 inch diameter
- 2 alcohol wipes
Conclusion
In conclusion, the Rockford Fosgate HD14-SBSUB is an impressive audio upgrade for Harley Davidson touring bikes. With its dual 10-inch woofers, high-output amplifier, and easy-access control panel, you’ll enjoy crisp, clear bass on your rides. It’s easy to install, compatible with several Harley Davidson models, and comes with a 1-year warranty. If you’re looking to take your audio system to the next level, we highly recommend the Rockford Fosgate HD14-SBSUB.