When you add on to your stock HD radio with Harley's BOOM amplifier and speaker, etc, Dealer Digital Technician Software update is required. In regards to aftermarket audio amplifier, speakers, etc, there is no mention of any update software needed on their instructions. Is this a way for the MOCO/dealers to charge you more when purchasing HD audio's accessories. It seems to me you are better off purchasing aftermarket. Just my two cents.

 

No flash needed for aftermarket amp IF you use the BIKETRONICS LINE LEVELERS.

You have a wider choice of components at a lot less money

 

If you are talking about rushmore bikes they all require either a dealer flash when using an amplifier or a line leveler device. The majority of aftermarket companies don't mention this because HD uses a proprietary headunit that is not common in the audio world. However, Arc Audio designed the Arc Moto amplifier specific to motorcycles and has advisory posted on which flash they recommend for use of their amp.