Adding Amplifier to stock Connext System

[jefhuf19]

In my boat, which could be different from year to year and model to model, the cockpit and swim platform speakers were wired in series. If the cockpit speakers are disconnected from the stock wiring, then the swim platform speakers won't get signal from the head unit as the circuit would be broken. I need to verify the wiring first with my meter but if all goes as expected, a shunt to connect the +/- wires (where they stock wires were disconnected from the cockpit speakers) to complete the circuit will work. But I need to verify wiring first for my scenario. If your swim speakers were on their own channels, then yes just leaving them connected would work as nothing has changed for them.

This is a series circuit:

View attachment 142377

Notice how the two speakers are connected to each other with only one +/- back to the amp/head unit. If one speaker is disconnected or removed, then the circuit is not complete and the second speaker won't work as it's not getting a signal.

Yamaha wires the speakers like this because the lower power 4 channel head units can't provide the current to drive two pairs of speakers in a parallel circuit where the current draw doubles, plus another pair (six total). Typically the head unit's built-in amp would overheat and pop a fuse or blow the outputs in the head unit requiring replacement.

Wiring them in series doubles the resistance which cuts the current draw in half so a 4 channel head unit can handle driving six speakers. But the two pairs in series have only half as much power output so they're noticeably lower volume compared to a pair running direct. You can set the fader to middle and ensure all volumes for zone 1 & 2 are equal - then listen to the speaker volumes at each location. The pair running direct will be louder and more full sounding at moderate volumes.

Got it, hadn’t thought about them being wired in series instead of parallel but makes total sense. Sounds like if you wanted to use factory outputs on the swim deck it would be easiest to just run some new speaker wires and cut/splice the harness.

 

[jefhuf19]

Actually I had the swim deck speakers on the "rear" channels so I could turn them off when cruising or not using the swim platform. The cockpit and bow speakers were wired in parallel so they were on while cruising.

I'll be making a slight change. I'll still run the cockpit and bow speakers on the "front" channels 1&2 like they are now, no changes there, but the extra mid-cabin speakers will be run from the "front" as well but on the 3&4 channels from the amp. The amp just needs to be switched to two channel input and wires run as needed. The stern doesn't need to be as loud and I can power them through the Fusion head unit on the "rear" using the stock wiring (just need to run a bypass for the wiring). This way I can still fade the stern out when cruising and keep the cockpit and bow speakers pumping with about 400w total - more than enough for loud tunes. The benefit of the mid-cabin speakers will be two-fold - more volume total plus more sound at the helm and passenger area so we're not blasting the rear-cabin and bow with high volumes when not desired. Passengers in those areas were getting blasted sitting beside the speakers while we still wanted more volume. This should balance it out nicely.

If you get tower speakers, you might want to consider more power for them - they need lots of juice especially if they're bigger units. 70wx2 to the towers isn't a lot of power unless they're smaller 6.5" speakers.

@212s, One other question for you, with the JL MX500/5 is there any "tuning" that you needed to do or was it pretty much ready to roll out of the box? It doesn't look like there are a lot of available adjustments as I assume you would turn the HP/LP filter off. Curious as I was also looking at the Rockford Fosgate amps and like their CLEAN technology that helps you tune for clipping.

 

[212s]

@212s, One other question for you, with the JL MX500/5 is there any "tuning" that you needed to do or was it pretty much ready to roll out of the box? It doesn't look like there are a lot of available adjustments as I assume you would turn the HP/LP filter off. Curious as I was also looking at the Rockford Fosgate amps and like their CLEAN technology that helps you tune for clipping.

Most of the same adjustments are there under a gasket sealed panel. I use the HP filter set at it's lowest setting to help filter deep bass that the speakers can't reproduce...saves a bit of power. I tuned the amp the usual way - turn the input sensitivity gain down and set the radio volume at 80 with the loudest input and turn up the gain until the amp peaks and then down a tad to keep it clean. I tuned the rear swim speakers down a bit too as they can only handle 50w. Here's a pic of the settings:

 

[jefhuf19]

Most of the same adjustments are there under a gasket sealed panel. I use the HP filter set at it's lowest setting to help filter deep bass that the speakers can't reproduce...saves a bit of power. I tuned the amp the usual way - turn the input sensitivity gain down and set the radio volume at 80 with the loudest input and turn up the gain until the amp peaks and then down a tad to keep it clean. I tuned the rear swim speakers down a bit too as they can only handle 50w. Here's a pic of the settings:

View attachment 142515

good stuff, thank you again!

 

[jefhuf19]

Got my MX500 installed along with a Rockford Fosgate P300.1 I had already for a sub I cut in by the port side seat. All worked great for the first couple times I turned it on in the garage but then the JL stopped playing sound but at the sub amp still plays. Both amps are powered and grounded through the same distribution block and both are connected to a remote turn on lead running through a relay. The JL green light is on and protect light is off...any thoughts on what to check or anyone have a similar issue?

Most of the same adjustments are there under a gasket sealed panel. I use the HP filter set at it's lowest setting to help filter deep bass that the speakers can't reproduce...saves a bit of power. I tuned the amp the usual way - turn the input sensitivity gain down and set the radio volume at 80 with the loudest input and turn up the gain until the amp peaks and then down a tad to keep it clean. I tuned the rear swim speakers down a bit too as they can only handle 50w. Here's a pic of the settings:

View attachment 142515

 

[212s]

Got my MX500 installed along with a Rockford Fosgate P300.1 I had already for a sub I cut in by the port side seat. All worked great for the first couple times I turned it on in the garage but then the JL stopped playing sound but at the sub amp still plays. Both amps are powered and grounded through the same distribution block and both are connected to a remote turn on lead running through a relay. The JL green light is on and protect light is off...any thoughts on what to check or anyone have a similar issue?

No issues with mine...pulled the cover off last weekend and everything is working fine. Double check the wiring is all good, including the speaker wires maybe?

 

[Bizywk]

hi, just saw the same issue in my 2019 ar240. where you able to find a new rca pre-out harness? from fusion, or elsewhere? or maybe a part number?

Ditto. Bumping @jthackman 's post.

I was able to pull my boat out of storage today and confirmed that my pre-outs were cut and insulated too. I contacted Fusion early this morning, but no answer yet. Did anyone find a different source for a replacement Pre-Out harness? I see plenty of on-line Pre-Out harness listings for other Fusion models but I can't tell if they are compatible. I really would prefer not to have the additional power draw and cost of a line converter.

Thinking about tapping the cut wires and adding my own RCA connectors. Has anyone done this? Does anyone know how I can verify the proper polarity?

 

[jthackman]

FUSION Wire Harness f/ MS-RA670 & MS-RA770 Stereo - Zone 1 & 2 (B Port-RCA) 010-12812-01FUSION, Boat Accessories, Boat Equipment - Boaters Marine Supply

Wire Harness - Zone 1 & 2 (B Port-RCA) Compatible with MS-RA670 and MS-RA770 stereos FUSION's Zone 1 & 2 Harness Wire for installation. WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more...

www.boatersmarinesupply.com

FUSION Wire Harness f/ MS-RA670 & MS-RA770 Stereo - Zone 1 & 2 (B Port-RCA) 010-12812-01FUSION, Boat Accessories, Boat Equipment - Boaters Marine Supply

Wire Harness - Zone 1 & 2 (B Port-RCA) Compatible with MS-RA670 and MS-RA770 stereos FUSION's Zone 1 & 2 Harness Wire for installation. WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more...

www.boatersmarinesupply.com

https://jetboaters.net/threads/2019-ar240-audio-upgrade.21424/page-5

both of these harnesses fit/worked on my MS-RA70NSX...
i've seen threads here of splicing on rca plugs...but the harnesses were easy