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QC Ultra 4-RM Amp Speaker Kit For Ultra Models

QC Ultra 4-RM Amp Speaker Kit For Ultra Models

SKU: QC Ultra 4-RM
  • Includes QC 475-RM "Quadcast" 300 Watt 4 channel Amplifier with G4 front and rear speakers
  • Kit fits FLH (Batwing) and FLTR Road Glide model bikes
  • No radio "re-flash' is required (Road Glide Ultra owners please see Note 2 below)
  • Cast aluminum 3D design gives exceptional thermal performance in high heat climates
  • Features proprietary  R.E.M.I.T. circuitry which gives superb FM reception from a class D amp
  • Supplied "G4" front and rear speakers are direct replacements for stock speakers
  • Unlike car audio-based systems, the radios fader control will continue to work
  • Includes metal mesh grill for all 4 speakers
  • Includes 100% plug and play wire harness
  • Very nice improvement over stock with minimal strain on the bikes charging system
  • All required hardware to complete the installation is in the box
  • Amp can easily link to Hogtunes REV 225-RM to add lower speakers or saddlebag lids later on
  • 3 Year warranty on amplifier
  • 20 Year warranty on speakers
  • Drag Specialties Part # 4405-0785


Note 1: The QC 475-RM Amplfier is a Class D design. It should be understood that ALL Class D amplifiers, regardless of brand, cause a reduction in FM reception. The QC 475-RM features a proprietary circuit design called R.E.M.I.T. (Reduced Electro Magnetic InterferenceTechnology) that Hogtunes believes gives the BEST FM reception available for any Class D Amplifier designed for a motorcycle.If you add a 2nd  amplifier to your system, reduction of FM reception is increased and is considered normal.


Hogtunes understands that some riders prefer the cosmetics of in-fairing antennas, however, it should be noted that NOTHING works as well as the factory antenna. If FM is an important part of your riding experience, we strongly advise against the use of any in fairing type antenna!


Note 2: From a sonic point of view, Road Glide Ultra has the correct flash, however, the factory flash in Road Glide Ultra makes the radio play considerably QUIETER than it could. Less signal out from the radio means less signal going into the amps. If you install this system without a reflash,it will sound great, but will NOT reach its potential volume. A radio reflash by a Techno Research dealer is required to make this system play to its full volume potential. An OEM Dealer reflash will not “fix” this, as the OEM flash looks at the bikes VIN and will re-install the same “quiet” flash. To find a Techno Research dealer near you, please visit or CALL US!





  • Bike Fitment

    • 2014-Current FLHTK Limited Ultra Classic 
    • 2014-Current FLHTCU Ultra Classic 
    • 2020-Current FLTRK Limited Road Glide Ultra  
    • 2016-Current FLTRU Road Glide Ultra 
    • 2014-Current FLHTCUG Tri Glide Ultra
    • 2014-2023 FLHX Street Glide
    • 2015-2023 FLTR Road Glide
    • 2018-2023 FLHT Electra Glide Standard Fairing (with factory radio installed)
    • For CVO Model Fitment Please Email



  • Included In Box

    • QC 475-RM 4 Channel Amplfier
    • Front and Rear Replacement Speakers
    • Front and Rear Replacement Metal Mesh Grills
    • 1 Mounting Plate for FLH (Batwing) Model Bikes
    • Fasteners for FLTR Road Glide Model Bikes
    • Plug & Play Wire Harnesses For Front and Rear Speakers
    • All Required Hardware to Complete the Installation
    • 1 Installation Manual
  • Installation Guide