Factory Harley Radio Integration Secrets for ‘14 & Up

Harley Radio Secrets - Stereo Upgrade


It is very possible to get great sound out of your ‘14 & up factory Harley radio. In fact, there are several performance advantages to keeping the factory radio that you could never get with an aftermarket radio. However there are a few things to know before you get started. This article is intended to be an aid to anyone looking to upgrade their Harley audio system with the new generation of radio. This article will give you a good grasp on how to properly perform a quality upgrade and how to avoid some of the bad information and practices that we see out there. The information in this article applies to all '14 & up Harley radios regardless of which model radio you have (touch screen, no touch screen, GTS, nav, no nav etc.) 

This guide covers most all aspects of this topic. Some of it can get a bit wordy, but if you are looking for definitive answers and spectacular results, read on. 

There are three primary issues with the factory Harley radio. All of which are simple to overcome if you know what you are doing and have the right equipment.

Issues that need to be addressed

  1. Frequency response. Harley loads wild EQ curves into the factory radio that you the user have no control over. This makes simply adding speakers and an amplifier alone without the correct Harley specific parts a total disaster. 
  2. Resistive load. When you remove the factory speakers and instead feed the radio output to an aftermarket amplifier or sound processor, the radio has no load and the output becomes unbalanced. A special resistive load needs to go between the radio and the next device (amplifier or processor). 
  3. Signal voltage. The output of the factory radio is designed to drive speakers directly. Before feeding that signal to an amplifier or sound processor you need to make sure that the device is designed for speaker level. All good amplifiers and processors are designed for direct speaker level signal input. If you are dealing with an amp or processor that requires a high to low level signal adapter, you are likely dealing with the wrong equipment. This is a major red flag!

The Quick Rundown 

You can fix all three problems with just two parts. 

  • Plug and play signal harness kit. This is a part that plugs into the factory radio harness and gives you an RCA connection at the other end. This harness has a special resistor network built right in that keeps the factory radio happy when using an aftermarket amplifier. American Hard Bag makes these harnesses. They are available from American Hard Bag or any of our 400 plus authorized retailers across the US. 
  • Sound Processor. This is basically an equalizer like the ones that used to be popular with old home stereos. A processor though works at the digital level and can also do a lot more than simple equalization. The correct processor kills two birds with one big stone because it not only straightens out the radios frequency response issues (EQ curve) it also converts all f the radios speaker outputs into high quality RCA type outputs that are directly compatible with all modern amplifiers.  

The following is a thorough explanation of how these parts work and how to select the best sound processor for your particular system.  


Frequency Response Is a Problem, but Not the Only Thing That Needs to Be Addressed.

Thinking that the radios frequency response (EQ curve) is the only issue is a common mistake. This is not the case. Flashing your bike can make it better, but will not resolve all issues.

Harley Radio EQ Curve

Harley radios have an EQ curve programmed into them. This curve can be real problematic for an aftermarket system because aftermarket speakers and amplifiers are engineered to be used with a radio that has a relatively flat frequency response. The graph above shows the frequency response of a Harley that originally shipped with two fairing speakers and no factory amplifier (red). The blue line shows the response after the same bike has been flashed. This bike has essentially been flashed for factory Harley equipment that the bike does not actually have in order to get the flattened frequency response.  


There are a few ways of dealing with the EQ issue.

  1. Best option. Use a stand alone DSP (digital sound processor). This is a digital device (EQ) that can undo the EQ that is programed into your radio and also allow you to re- EQ your sound to your taste. This is really the ultimate solution. There are several manufactures out there that make these devices.
  2. Use a plug and play device that will flatten the frequency response and lower the signal voltage. It is our experience that these type of devices can be hit and miss and are always a serious compromise. They do not seem to work well with radios that are flashed for factory Harley amplifiers and they seem to work with some aftermarket amplifiers but not others. You never really know exactly what you are getting from these voodoo boxes.  
  3. Have the radio flashed. The friendly flash is not from Harley at all. There are radio flashes that the Harley dealer has access to that are more friendly but none of them are correct. The only correct flash available comes from a computerized flashing system made by Techno Research and was developed by Rockford Fosgate. Techno Research sells their $900 flashing system to bike shops and car audio shops. Rockford Fosgate has a program where their authorized dealers can get the techno system and the proper training if they sign up for it. Rockford keeps a list of all of the shops that participate. So you can go to www.RockfordFosgate.com and find the latest list and locate a dealer near you. Some factory Harley dealerships also have the Techno Research system in addition to the factory system. So you can check with them as well. Be aware though that it is technically against Harley corporate policy to flash a bike for anything other than factory options that are actually on the bike. So if you run into resistance at your local dealership don't be too surprised.  

Recommended processor options

 1. Rockford Fosgate DSR1 


This is currently the most attractive option on the market in my opinion. The DSR1 packs in all of the best features that you could ask for (all but one, read on). This processor is wildly popular and for good reason! 

  • Small enough to fit in any fairing.
  • 8 channels of output.
  • Separate parametric 31 band EQ for each of it's 8 channels of output!
  • A simple 7 band EQ for novice users.
  • Digital crossovers for each channel capable of up to 48 db slopes that can be set at any frequency your heart desires for any channel.
  • 2 or 4 channel input with selectable output channels 4 through 8. 
  • Low or high (speaker level) inputs. This means that you can plug it into a factory radio or use it with an aftermarket radio. 
  • Operated by your smartphone via Bluetooth. NO PC REQUIRED!
  • An unlimited number of setting files can be saved to your phone. You can save every setting all at once and never fear of losing your tune.
  • Setting files can be emailed or texted to or from anywhere in the world. 
  • Beautiful and friendly touchscreen interface. 
  • No knobs or buttons on the outside of the unit. All settings are done remotely by your phone, so you don't need to take the fairing off if something needs to be changed. 


This article was originally written 3 years ago and a lot has changed since then. We love the DSR1 processor from Rockford Fosgate so much that we no longer recommend anything else. We have installed thousands of these units and have gone through the effort to create a setup file with a counter EQ curve for our customers and customers of our authorized dealers that flattens out the frequency response of the Harley radio to within 1 db from 45 to 17 khz. This would not be possible with most any other processor. The radical 23 db swings in frequency is far too much for most any processor to deal with, but the engineers at Rockford Fosgate had the foresight to put an unusually capable parametric EQ feature in the DSR1.  

  • Does away with the need for a radio flash for most all bikes that shipped with 2 speakers and no Harley amplifier.
  • Counter curve applied to all 8 channels
  • Saves endless hours of tuning time. Even with all of the fancy equipment in the world at our disposal, this took a lot of effort and thorough testing on our part to get this right. 
  • Free with DSR1 purchase form American Hard Bag or an authorized American Hard Bag dealer.

Factory Harley Radio Frequency Response

American Hard Bag counter EQ applied ↓

American Hard Bag Counter EQ Curve for Factory Harley Radio

Resulting settings on the DSR1 ↓

Applied American Hard Bag counter EQ curve for factory Harley radios

    Resistive Load. This is where many go wrong.

    Smoothing out the frequency response of the radio will do you no good if the factory radio distorts when you turn the volume up. What happens is that the radio clips (distorts) at a low volume when the factory speaker has been removed from the bike. This is because the amplifier built into the factory Harley radios is designed to drive a speaker and not designed to drive the inputs of an amplifier or processor. The resistive load needs to be lowered. Arc Audio has a great article explaining this problem that you can read here.

    Audiocontrol also has a similar article that you can find here. 

    Load Resistors



    The American Hard Bag Solution

    We have come up with a plug & play solution that remedies this problem by combining 3 parts. 

    1. Load resistors
    2. Rockford Fosgate RCA to speaker wire adapters
    3. Plug & play Harley radio connectors

    We build a single part that converts the factory Harley plugs to RCA and adds the required resistance for a clean distortion free signal. These parts can all be purchased separately, but we offer a single part already put together.   

    Front radio interface harness for factory Harley radioRear interface harness for Harley Davidson radioFactory Harley radio interface harness for Ultra models

    Additionally we include the opposite side of the Harley plug that allows you to make your amplifier speaker outputs plug & play with your fairing speaker pods.


    We make these in three varieties

    1. Front speaker (shown above).
    2. Rear speaker. You can use this version to add rear speaker outputs to a bike that only came with two front speakers (must be flashed for 4 speakers). The connector for this harness is in the fairing behind the radio in a single 4 pin plug.
    3. Ultra. Use this version on bikes that came with factory tour pack speakers. The rear speaker output from the factory radio on these bikes is only available under the seat back near the tour pack. This adapter is a T harness that goes between the tour pack and the bike harnesses and runs the signal back up to the front of the bike in the fairing where it terminates as RCA connectors.


    If your radio is flashed for 4 speaker output, you must use load resistors or the above mentioned plug and play adapters on both front and rear outputs of the radio. Even if you don't use the rear outputs. If your radio is only flashed for two speakers you will not need load resistors on the rear outputs because they are defeated in the radio. 


    Speed Controlled Volume

    The speed controlled volume feature increases volume of the radio as your speed increases. This is a cool feature, but is not a good thing if you have an aftermarket amplifier. We recommend that you turn this feature off. Simply go through your audio settings and turn it off. 

    That's it! 

    Use a DSR1 and the DSR1 signal harnesses that we have designed and your factory radio will be plug and play with your aftermarket stereo system. 

    Note: All bikes that have factory amplifiers require some additional adapters. Give us a call and we can set you up with exactly what you need for your particular bike. 

    For assistance with installation and system setup

    Phone: 1(888) 311-0016

    Email: AmericanHardBag@gmail.com