One thing that is absolute about Harley enthusiasts is they don’t tolerate hanger-on-ers lingering around their bikes. They have even less patience for people working on them. Such is the case of Mark MacDonald’s FLHTCUSE2 Electra Glide Screamin Eagle, seen around the roads of Marshfield, MA. Mark’s is a great guy, but if you are not a Harley certified tech, you better have a serious list of references – the bearded and riding a HOG type of references.

When Mark decided it was time for an audio upgrade, he called Derek at Sound In Motion. Derek Kenney, Owner of Sound In Motion, spent several years with the MB Quart brand in Walpole, MA. Derek was part of the product development team. When the company moved west, he finally got to realize his vision of a custom high end audio shop – for the MASS’  


First up, the system challenge was converting the stock Harley 5.25 inch coax to the larger MB Quart Z-Line 6.5″ coax called the ZK1-116.

Derek is checking out the stock system in the Harley.

Derek increased the size of the stock opening from the 5.25 inch speaker to the full 6.5 inch to accommodate the Z-Line MB Quart 2 way. Sound In Motion is located in Allston, MA – a suburb of Boston. Mr. Kenneyowner says, “Installs of any kind for the HOG is tricky. They want everything to look stock like the day is came out of the factory, but they want the audio quality improved dramatically. That is why I choose MB Quart for Harley audio upgrades.”

The Z-Line 2-ways are incredible. Featuring a 1.4 inch (38mm) Titanium Dome Tweeter with a Removable Phase Lens an Oversized Thermal Formed Cone with a Nylon Surround all mounted on a PZ66 Composite Basking with Glass Fiber Reinforcement. The benefit of all this technology is an unbelievable sounding speaker. This is the classic high end MB Quart sound quality with modern innovation and materials.


Next up, power. The guys packed the super compact NA1 MB Quart powersports amplifiers. There are three models, for the Screamin Eagle powersports 2 channel amplifier into the Fairing. The team at Sound In Motion chose the NA1-400.2 for its size and killer sound quality. The chassis measures,  5.5″ x 3.7″ x 1.7″ (14 x 9.4 x 4.4cm) – that is pretty small.

Perfect for motorcycle installation, the NA1 series of amplifiers are designed with sealed and removable system connections to minimize exposure to the elements.

Plus, being a full range Class D the amplifier gives plenty of volume on a full ride, without overheating. The amplifier is pushing 400 watts out of that little chassis.

Follow Sound In Motion on Facebook to see all their incredible work. You can see a few installs and read customer reviews on their Yelp page too.

Learn more about MB Quart Audio at