Stereo Install Advice

Shawn

Just Hanging Out
Location
Holly Day
I'm not a pro when it comes to a semi complicated stereo upgrade so I'm seeking some advice from the wizards on this site. This stereo upgrade is for my boat. I have 4 pairs of speakers, two in the front, two in the rear and four in the cockpit. I will also have two subs in the cockpit.
Before I drop 2k in amps and subs and a head unit can anyone tell me if I have the right combination?

Stereo: Fusion 750
http://www.fusionentertainment.com/marine/products/750-series/ms-ud750

JL Audio Mono for the subs
http://www.jlaudio.com/m600-1-marine-audio-m-series-amplifiers-98273

JL Audio for the speakers
http://www.jlaudio.com/m400-4-marine-audio-m-series-amplifiers-98271

I'm fairly confident that is will work, just looking for a little feed back from this offroard board for my watercraft.... :D:D
 

Bart

Registered User
Location
Arm Utah
Sorry I won't be much help but I'm subscribed. Someday I want to add a system like this to my boat.
 

Cody

Random Quote Generator
Supporting Member
Location
Gastown
I'm not really sure what sort of pre amp outputs that stereo has. It say 4 (1 L/R pair per zone) but it doesn't say the amperage or anything useful about them. Thats fairly important information, as ideally you would want at least 3 (f/r and sub) and the higher the amperage the better (4 amp is better than 2 amp, and 4 amp non clipping is awesome). Think of it like this, the smaller the audio signal is, the more your amp has to work with to make it sound big. It's like taking a picture and blowing it up....the smaller the original is, the worse quality the blown up version will be.

As for the sub amp, that will work so long as your subs will wire in at 2 ohm (single 4 ohm coils, or dual 2 ohm coils per). You can run the 4 cockpit speakers on one half of the 4 channel amp at 2 ohm, then the rest of the speakers will be on the other channel...is that the plan? The F/R speakers would be tied together, and the cockpit speakers tied together so you could fade in or out of either, but you couldn't fade from F-R of the boat....unless that deck has some other functionality that I'm not familiar with.

JLRockies is the master of this stuff. You should PM him.
 
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bobdog

4x4 Addict!
Location
Sandy
I'm not really sure what sort of pre amp outputs that stereo has. It say 4 (1 L/R pair per zone) but it doesn't say the amperage or anything useful about them. Thats fairly important information, as ideally you would want at least 3 (f/r and sub) and the higher the amperage the better (4 amp is better than 2 amp, and 4 amp non clipping is awesome). Think of it like this, the smaller the audio signal is, the more your amp has to work with to make it sound big. It's like taking a picture and blowing it up....the smaller the original is, the worse quality the blown up version will be.

I will agree that a 4 volt preout (I am guessing you meant volt not amps) is preferable, and all head units that have any SQ aspirations (which these days are few and far between) will output 4 volts. When you say that a lower output signal is like taking a small picture and blowing it up losing resolution, that is just wrong. What the higher outputs will allow is playing with gain structure to lower noise (turning down the amp gains will lower noise from the head unit but there really should not be any to begin with). With proper install and good equipment all other things being equal a 2 volt head unit would most likely sound identical to a 4 volt output.
 

Cody

Random Quote Generator
Supporting Member
Location
Gastown
duh, ya, I meant volt. Got in a hurry and haven't really played in audio stuff in 10 years. Wouldn't the "noise" associated with over amplifying an audio signal be similar to the distortion in over enlarging an image? Maybe I'm misunderstanding the principle, but lowering the gain of the amp doesn't impact the amount of noise coming from the source, it just lessens the amount that the audio signal is amplified. I think in this modern day with the amount of compressed audio that is being used, it becomes even more critical to match the gain on the amp to the input signal since the audio is pretty dirty...and you're right that when set correctly it shouldn't matter if the input is 2 volt or 4 volt (other than how hard the amp is working, which in some situations can also impact sq).

This is all well and good, but in a boat I think SQ is probably out the window.
 

bobdog

4x4 Addict!
Location
Sandy
duh, ya, I meant volt. Got in a hurry and haven't really played in audio stuff in 10 years. Wouldn't the "noise" associated with over amplifying an audio signal be similar to the distortion in over enlarging an image? Maybe I'm misunderstanding the principle, but lowering the gain of the amp doesn't impact the amount of noise coming from the source, it just lessens the amount that the audio signal is amplified. I think in this modern day with the amount of compressed audio that is being used, it becomes even more critical to match the gain on the amp to the input signal since the audio is pretty dirty...and you're right that when set correctly it shouldn't matter if the input is 2 volt or 4 volt (other than how hard the amp is working, which in some situations can also impact sq).

This is all well and good, but in a boat I think SQ is probably out the window.

Lowering the gain of the amp does lower the noise floor (the noise that is there whether there is signal or not and when there is no signal is when the noise is noticed) Lets say the preamp in the head unit is noisy or the interconnects are picking up noise from the vehicle, turning the amp gain down will lower this noise. If the head unit can output more voltage you can turn down the gains more, lowering the noise. I have not had a boat for a very long time, but the times the stereo was enjoyed the boat was sitting silent. I'm getting pretty old but almost my entire music collection which is extensive is uncompressed meaning neither brickwalled in mastering or encoded in lossy formats like MP3 ect. Good sounding recordings are out there.
 

bobdog

4x4 Addict!
Location
Sandy
A good example of what I am talking about is the preamp in my main home system. It will operate in active or passive mode. In active mode it has gain and will output a higher voltage signal to the amplifiers. In passive mode it will output less. The fact is I have a hard time hearing any difference between the two modes the only noticeable difference being the position of the volume knob at a given volume. Both modes are dead silent even with 105db efficient speakers.
 

Shawn

Just Hanging Out
Location
Holly Day
Thanks for all the posts, but I'm not sure how they will help me.... I guess I will just keep researching, I just sometimes don't understand this talk...
 

Cody

Random Quote Generator
Supporting Member
Location
Gastown
OK, so I downloaded the manual for that deck. Each "zone" gets L/R and sub outputs it appears. So you can control audio output to run Front, Rear, and Cockpit all independently provided you can amp them independently. The amp only has 4 outputs, so unless you buy a 6 channel amp, you're really only going to have 2 "zones", which I'm guessing would be f/r and cp (you wouldn't be able to fade front to rear, but you could fade in/out of the f/r channel and the cp channel). Does that make sense? If you had another 2 channel amp, then you could utilize all three zones and control them independently.

Then, you'd have to decide which zone you want the sub audio tied to. If plan on having the same audio signal going everywhere, then it doesn't really matter which zone the sub signal comes from.

Then, then, you'd want to make sure the number and impedence of voice coils (speakers) wired to each channel is going to work with the amp. If each zone has a pair of speakers each (3 zones x 2 speakers per), then you'd either have to find 2ohm speakers for the channel that has 4 speakers on it, or add a 4th set of speakers so that both sides of the amp see the same resistance. I don't believe that 4 channel will run 2 channels at 2ohm and 2 at 4ohm...

Does that help at all?

edit: as another thought, since the cockpit is probably enclosed, you could perhaps run those speakers off of the amp that is in the deck itself, then use the 4 channel for the f/r speakers. Maybe that is what you had intended all along?
 
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Shawn

Just Hanging Out
Location
Holly Day
Thanks Cody,
Let me tell you how it is currently wired, probably wrong.... The deck has three zones with the cockpit handling the 2 pairs of speakers and a single sub. the other two zones control the front and back. The amp is a 4 channel amp http://www.fusionentertainment.com/marine/products/amplifiers/FM-504
and the speakers are 200 w 4oms http://www.fusionentertainment.com/marine/products/speakers/ms-fr6021 This system was installed by the manufacture, right or wrong. Since the amp is blown and the deck is outdated I would like to upgrade the amp/s and add a second sub. I can't do all this and buy new speakers, at this point.
I would really like to run JL Audio and I'm very limited to my choices for a marine deck.

Again, thanks for taking the time to help me, I'm happy to start over and rewire the boat, I just need to know what will work the best.
 

Cody

Random Quote Generator
Supporting Member
Location
Gastown
So is the deck powering the cockpit speakers and the sub? I'm assuming the sub would be self powered if that is the case.

If that is the case, then just swapping out the deck and amp would give you the same functionality you have currently. Adding the extra sub shouldn't be a big deal...just require a distribution block for power and some pretty easy and straightforward wiring. You would then want to adjust the gains on the new amp, but that's not terribly difficult either.

Like I said before, it's been several years since I've played with car stereo stuff for a living, but I'd be happy to come up and lend a hand if you need it.

Cody
 

Jesser04

Well-Known Member
Location
Kaysville Utah
If you are going to us JL I'd look at a quality head unit I'd look at car/truck units. I don't know what kind of boat you have but if you have a storage/travel cover a marine unit is not necessary. One thing to think about is if you put a new sub in you will more than likely have to build a new enclosure. You can buy the best stuff money can buy and if the enclosure is not to spec it will not sound good.
 
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Jesser04

Well-Known Member
Location
Kaysville Utah
My is .02 don't buy marine anything. If you want JL get a set of http://www.jlaudio.com/12w3v3-2-car-audio-w3v3-subwoofer-drivers-92153. You stuff won't get wet enough to matter. I agree with Cody you can't go wrong with alpine or pioneer. I like pioneer just because I've owned them in the past and it's what I know. I have a 23' deck boat the stereo is about 4-5 years old we have done a few since then and learned a lot. I hope to redo mine before summer but I'm running out of time and I leave my boat at the gorge so once it's gone I can't do it. The most important thing in a boat like ours is the enclosure it will make or break you stereo. If your boat is laid out like mine I'd put them right in front of the drivers seat firing from right to left underneath your windshield. Call me if you'd like I think I can help you a little.
 

DaveB

Long Jeep Fan
Location
Holladay, Utah
Thanks Jesser, The boat is a deck boat, just a basic open boat, but I can completely cover the cockpit area in a storm. In your opinion, who makes a quality head unit? Bother areas for the sub are large areas so I was planning on using infinite baffle subs http://www.jlaudio.com/m10ib5-sg-wh-marine-audio-m-series-subwoofer-drivers-91733

If you use infinite baffle speakers make sure the sound from the back of the speaker can't make it out to the front of the speaker or you will cut out a lot of sound. also don't combine them in the same area with an infinite baffle main speaker or you will get distortion. I use a marine unit on my boat since rain isn't the only source of water.
 

Jesser04

Well-Known Member
Location
Kaysville Utah
Correct me if I'm wrong. Your boat has a set of 6.5's in the open bow and a set in the cockpit? If you want JL here is what I'd get.
2 sets of these. http://www.jlaudio.com/car-audio-speakers-c2
Power them with this. http://www.jlaudio.com/xd400-4v2-car-audio-xdv2-amplifiers-98602
2 of these. http://www.jlaudio.com/12w3v3-2-car-audio-w3v3-subwoofer-drivers-92153
Power them with this or the 1000.1. http://www.jlaudio.com/xd600-1v2-car-audio-xdv2-amplifiers-98604

i don't know what your stereo sounded like before you blew the amp but this setup will bring the party.
 

Shawn

Just Hanging Out
Location
Holly Day
Boat has a set in the front, two sets in the cockpit and one set near the swim deck in the rear., so 8 total speakers One sub is mounted in the cockpit under the passenger side seat facing forward and I was going to mount the second under the dash facing the driver above the foot rest. Both sub enclosures have over 9 square feet of air.

Once again, Thanks,
 
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