Question about install on my boat!

[Gene3x 10+ year member]

OK, I have a Kicker 850.4 running Defcon IV's at a 2 ohm load on one side and the other side is pushing 6 interior coaxial speakers wired in series. The amp cuts out if I crank it up for any length of time.

Also, pretty sure it is not related (but I am no expert), I get a engine noise type whine (with engine not running) from the speaks with nothing on but the amp on. I think it might be the fan in the amp? Could the problems be related?

An amp of this power and rating should not cut the amp off right? It is rated at a 2 ohm load.

I am close to saying screw it and buy a nice Xtant X604 competition amp I can get a decent price on. Do I need to spend the money? I am thinking maybe I need a larger cleaner amp because at a high volume I can hear distortion and can't imagine it could be the amp. Could I need more power?

The Defcon's are super high end image dynamic speakers and should handle alot more clean power.

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[n2audio 5,000+ posts]

what's your power supply like? Upgraded alt/batt?

Generally boat alternators are unusually small -- 50-60A. An a/b amp of that size running near minimum impedance is going to draw a LOT of current, and assuming you've got 30-40' of pwr/grd wire it could just be a low voltage issue.

 

[azimuth 5,000+ posts]

what's your power supply like? Upgraded alt/batt?Generally boat alternators are unusually small -- 50-60A. An a/b amp of that size running near minimum impedance is going to draw a LOT of current, and assuming you've got 30-40' of pwr/grd wire it could just be a low voltage issue.

exactly correct. xtants are awesome amps. i have the one in my sig for my comps. just by itself, with the sub amp off it dims my headlights. excellent amps, but they need power.

 

[bri487 5,000+ posts]

OK, I have a Kicker 850.4 running Defcon IV's at a 2 ohm load on one side and the other side is pushing 6 interior coaxial speakers wired in series. The amp cuts out if I crank it up for any length of time.Also, pretty sure it is not related (but I am no expert), I get a engine noise type whine (with engine not running) from the speaks with nothing on but the amp on. I think it might be the fan in the amp? Could the problems be related?

An amp of this power and rating should not cut the amp off right? It is rated at a 2 ohm load.

I am close to saying screw it and buy a nice Xtant X604 competition amp I can get a decent price on. Do I need to spend the money? I am thinking maybe I need a larger cleaner amp because at a high volume I can hear distortion and can't imagine it could be the amp. Could I need more power?

The Defcon's are super high end image dynamic speakers and should handle alot more clean power.

i wouldnt go xtant, i had problems with them shutting off in the extreme temps in my boat. swapped out my xtant 4.4 for a zapco ref 1000.4 and it is a world of difference, the batteries will die before it shuts off. chances are you are experiencing an impedance drop, low voltage, or just too high of temps and it is causing the amp to cut out. what kind of boat do you have btw?

 

[Gene3x 10+ year member]

I have a Supra 24 SSV and everything is mounted in the front storage compartment. The wire run is short because the batteries are there also. They are regular cranking batteries but I have some stingers on the way. Could that still be what it is? The other amp is a PPI DCX1500.1 running just one W3... **** I knew this was gonna happen once I got into it. Do I need to replace my alternater from stock?

So a drop in voltage would definately cause it to distort?

I am deciding to go with a bigger amp (maybe a SOUNSTREAM TRA960.4) or go with a separate amp (maybe a Soundstream Tarantula Tr 700/2) for the towers and add a JBL GTO75.4 that I have laying around for the interior coaxials.

 

[n2audio 5,000+ posts]

Bad a$$ freaking boat...

So the batteries are several feet from the alt?

The wires to the amps may be short, but if you've got 40' of pwr/gnd wire between the alt and batts that's where the voltage is dropping.

Even if you have a big alt (which you may on that engine) your amps may only be seeing 13v or so, and probably

It would be helpful to know ---

1) what size alt you have (how many amps)

2) what voltage you're getting at the amp terminals under varying conditions -- engine off w/and w/o stereo, engine idling w/and w/o stereo, at ~2k w/and w/o stereo.

 

[Gene3x 10+ year member]

Thanks man, I spend alot of time on her and am coming off a broken ankle from a half cab roll so I figured I would do my install while I am down! It has just been awhile since I did any sort of serious install.

I will check the voltage and see what size alt is on there. Is there anything else I can check in the down time? It is definately not the way the speakers are wired correct?

 

[n2audio 5,000+ posts]

might want to verify how the speakers are wired, and that you didn't get wires crossed somewhere which may have changed the impedance significantly. With that many speakers it sounds like a lot of opportunity to mix things up somewhere along the lines.

Are the defcon's 2 ohm speakers or do you have 4 of them?

And you have 6 speakers wired on the other 2 ch?? 3 on each channel?? And all in series?

 

[Gene3x 10+ year member]

Yes that is correct. I have 3 speakers wired in series on the rear two channels and the Defcons on the other two. They are 2 ohm speakers.

 

[bri487 5,000+ posts]

in my boat i run three group 31's. two just for the system and one to start the boat. i have a built in 3 stage charger that charges each individually. go home plug it in and call it a day. stock alternator. i can run my whole system day and night and still start it up on the same two without ever touching the one for the boat. i have 1200 watts on the sub and 1000 on the highs. i am on it full bore all day long too. never shuts off. no problems whatsoever.

 

[Gene3x 10+ year member]

That is esentially what I will be running. So with two Stingers and an isolator I should be fine to not have to worry about a HO alternator?

I just looked at Indmar's website and my alt runs at 40amps when the boat is at idle and 90 on the top end. That should be plenty huh?

 

[bri487 5,000+ posts]

That is esentially what I will be running. So with two Stingers and an isolator I should be fine to not have to worry about a HO alternator?
I just looked at Indmar's website and my alt runs at 40amps when the boat is at idle and 90 on the top end. That should be plenty huh?

i would ditch that isolater immediatly. when running a system in a boat for extended periods of time, you tend to kill the batteries that you were running on. go to start the boat and the isolator clicks over to the charged batteries, unless you really drained the batteries that you were running on and they dont have enough power to amke the isolator click over. a perko switch is a safer route to take, and an on-board charger with a regular 3 prong pigtail on it will definitly get you the most out of your system. it is maintenence free, just plug it in, it is a 3 stage so you can leave it plugged in for weeks/months at a time if you forget and it wont harm a thing.

 

[Gene3x 10+ year member]

Sorry it is a Perko switch. An isolater is just automatic right? on board charger it is then.

 

[bri487 5,000+ posts]

Sorry it is a Perko switch. An isolater is just automatic right? on board charger it is then.

yea, perkos are much safer. you have the one with battery one, two and both right, the manual switch. dont ever switch it to off when the boat is running, and as a general rule, i always leave mine on two (aux for system) even two, because they will start to boat and i always have one in reserve for emergencies. if i kill them, then i go to one.

 

[Gene3x 10+ year member]

Is there a Perko switch that will let you run 3 batteries off of it?