Here is a detailed walk-through of Audio System upgrades I'm doing to my FSH 252.
Before I begin, I am a Master Electrical Contractor with many many years of residential, commercial, marine, and car audio systems.
Please don't attempt this yourself! ?
I am not responsible if you damage your boat.
I've been unhappy with the system that came with the boat, so I'm adding a Kicker KMC5 head unit.
The FSH 252 comes with 6 Wet Sounds 6 1/2" Speakers, so the KMC5 is the perfect choice as it outputs 25watts x 6 @ 4 ohm.
The Wet Sounds speakers are 4 ohm by the way.
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On this hot summer day, I was glad I had my Klein battery powered fan!
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Step 1: Remove and later relocate the 12 volt outlet and aux Jack.
Make sure your battery is off!
These simply unscrew from the back.
For whatever reason the aux Jack unscrews in reverse.
I'll be reinstalling the 12v Outlet to a different location soon.
The aux Jack is plugged in with an RCA cable behind the Connext screen.
I will not be reusing this.
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Step 2: Drill 3-in hole.
The Kicker unit comes with a rubber gasket that also acts as a template for the hole we need.
(Make sure there are no wires behind this area!) You'll want to run a pilot hole in the center first.
Afterwards run your hole saw in reverse for a moment to get through the gel coat without cracking it.
Then go ahead switch the drill to forward and finish drilling your hole.
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Step 3: Insert the head unit, and drill 4x small holes for the bolts.
The unit came with wood screws so I picked up 4x 6x32 pan head bolts with nuts and lock washers.
Finish it up with a little bit of lock tight on the nuts.
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Step 4: Disconnect and remove the Wet Sounds amplifier.
Make sure your battery is off!
Using a small allen wrench remove the left side plate on the wet sounds amplifier, then using a larger allen wrench remove the red and black power wires.
There are two quick connect plugs on the amplifier.
The bottom plug feeds the speakers.
The top plug feeds from the Connext screen.
Unplug both of those and remove the amplifier.
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Step 5: The 12v Power Wiring.
All of this should be in split tubing. (Mine is on order, and i'll be installing it soon.)
Attach #12 red & black from the KMC5 to the power wires you just disconnected from the amplifier.
I recommend you put this into a fused distribution block.
Step 6: The Speaker wiring.
(From here on out I will be using the following tools and parts: Klein 3005CR ratcheting crimp tool, Klein 11061 wire strippers, #16 heat shrink butt connectors.
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Green + Green/Black - Rear Left
Blue + Blue/Black - Rear Right
White + White/Black - Front Left
Grey + Grey/Black - Rear Right
Bottom White + White/Black - Zone 2 Left
Bottom Grey + Grey/Black - Zone 2 Right
The bottom plug to the amplifier has four sets of wires: white/white black, gray/gray black, blue/blue black, green/green black.
This gets a little tricky because white and gray are not feeding directly to the speakers.
They are combining the front seating area speakers with the speakers on the side of the center console.
What you'll want to do is remove the white hard plastic at the bottom of the center console, and find the black split tubing coming from the front seating area.
Inside you will find white and gray speaker wires. We will be calling this zone 2.
Run two sets of speaker wires from the kicker to these, using butt connectors.
Solid white is positive; white with black stripe is negative.
Using a heat gun, carefully heat the shrink tubing.
Afterwards reassemble the the white hard plastic as we are done underneath the console.
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Now cut the speaker wire connector from the amplifier, leaving about 6 in of wire so this can be reinstalled if needed in the future.
Do not cut the top plug from the amplifier as it's feeding into the Connext screen.
It has a red plug so it's easy to spot the difference.
We will only be using the blue and green wires at this connection.
Run 2 sets of speaker wires from the KMC5 over to the recently cut amplifier wires.
Blue is the top right tower speaker, green is the top left tower speaker.
Connect those to rear left and rear right respectively.
Run another speaker wire from the Kicker directly to the left center console speaker
At this speaker, cut back the white/white black 6in from the quick connect plug.
Connect this speaker to Front Left on the KMC5.
Connect the Right center console speaker directly to the KMC5, on Front Right.
Finally connect the FM antenna.
Heat all of the heat shrink connectors, tidy everything up with zip ties, and you are done!
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Final Thoughts:
I've turned on the Loudness feature on the KMC5, and set the high pass filter.
The result is rich sound, with powerful mid bass.
It brings to life these Wet Sound speakers in a way Yamaha did not.
Even at full volume, there is little to no distortion.
At this point some of you would not even opt for a subwoofer!
It sounds great!