MasterCraft X-55
Click on any of the pictures below to see a larger version.


MasterCraft X55 gets a redesign of the factory audio system.

From the factory this MasterCraft came with the JL Audio system. At this time, the JL Audio speakers represent the best in marine audio from a sound quality standpoint. However, many MasterCraft owners have not heard the full potential of the JL Audio marine speakers, particularly in the area of subwoofer and tower speaker performance. This is because they are underpowered. You're hearing the limitations of the amplification and not the speakers. Not that the JL Audio amplifiers aren't excellent in every respect, there just isn't enough of them. So we made a number of alterations and additions while maintaining 100 percent of the existing equipment.


The X55 came with two JL Audio six-channel amplifiers. We moved the port side amplifier over to the starboard helm console locker so that it was better protected from the occassional roller over the bow. A new amp mounting panel supported the two amplifiers plus a third six-channel addition. Also, serviceability is made easier in this large compartment. The power distribution was as follows:

One JL Audio six-channel amplifier drove six 7.7-inch component speakers highpass with a discrete channel for each of the coaming speakers (one pair in the bow and two pair in the cockpit). Four channels were bridged into two and drove dual 10-inch free-air subwoofers lowpass.

Eight channels were bridged into four and drove four 7.7-inch tower speakers highpass. So that results in around 800 total watts to the tower, 400 watts to the collective subwoofers and over 400 watts to the collective in-boat fullrange speakers. It was a good balance.


However, distributing six 2-volt preouts to eighteen channels of amplification was going to leave us shy in the dynamic capabilities. So to avoid dynamic compression and really open up the music's contast and clarity, we added six channels of JL Audio 7-volt line drivers.

Also, a heat-formed ABS removeable panel next to the line drivers provide the concealed power distribution blocks with protection from items stored in the locker.


Two large DC circuit breakers were installed at the power source. Upgrading the supply cabling for the amplifiers was one of the more important steps in getting the factory system up to its potential.


A second JL Audio free-air 10-inch subwoofer was added next to the factory-installed sub. We were not happy with the way the factory sub location juts out into the center of the cockpit. This invites cancellations off the exterior and coincidental boundaries of the interior. Recessing the sub into a corner or on a perimeter surface would have been more productive. However, we elected to place the second sub right next to the factory location in order to maximize the effects of compound loading. In contrast, a second and dissimilar location would have created a non-uniform phase response where the two woofers would not have summed as effectively.

We added thick baffle rings concealed behind the subwoofers in order to get an extremely rigid mounting surface. And, we added dual runs of 2-conductor 12-gauge to feed the woofers. In any case, the factory wire needed upgrading.


After tuning the system, the sound transformation was night and day.


The tower speakers had no difficulty projecting to 80 feet. While not quite as loud as some of the larger HLCDs, with the added power (200 watts per speaker) they really reached out. But, the sound quality experience of lounging or swimming around the boat at rest is now unparalleled.

Doubling up the subwoofers with double the power, improving the baffle strength and upgrading the power and speaker cabling produced bass that reached the lower registers and hit with authority.

I think my favorite part of the system was with six in-boat 7.7-inch speakers. The midbass attack was as good as it gets.

With dialing in just a little residual output from the tower speakers, the in-boat volume could play loud enough without clipping to hurt you.


While the boat has a helm remote control, the boat owner wanted the source unit moved to the driver's side so he had better access to all functions. The underdash enclosure also got fitted with an exposed sub level control and an iPod storage pocket.

A cover panel was installed over the previous source unit location in the head.

The transom courtesy light was changed out to blue as were all the other interior lights. Plus, we added a few more.


A light was added on a separate circuit to illuminate this switch panel.


Step light at front of bow and step lights in the pass-thru between the helm consoles.



Forward and rear cockpit step lights.



Courtesy lights in bow and cockpit coaming pockets.



Factory underwater lights.


Blue LED lgiht rings on factory tower speaker pods.



Upon inspecting the two inside factory tower pods we discovered that these particular pods (also house halogen lamps) were not sealed air tight. In fact you can see daylight through the front of the pods. The halogen lamps must be accessed and serviced from the rear of the pods so we created a removable aluminum plate that could be fully sealed via a foam gasket.

The pods were drilled and tapped to accept machine thread screws.

With this issue resolved, the power handling and midbass of any speaker whether it be the factory JL Audio or a HollowPoint HLCD replacement is dramatically improved.




We did replace the factory tower speaker with the Bullet HollowPoint 770 HLCDs.

These dropped into the factory pods and used the previous light rings. White spoked grills tied in well with the factory JLs throughout the boat.

The big difference came in the HLCDs ability to project with absolute authority at 80 feet while competing with wind and engine noise.

Small aluminum caps were installed to cover and seal up the prior tweeter pod provisions.

Earmark Car Audio