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Powering amp for sub woofer

TomCat

TomCat

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Does anyone know if you can use one of the unused switches to connect power to an amp to drive a sub woofer? 2020 R25. I want to know if the switch can handle the load. The power line from the Amp has an inline fuse.
 
NO!

I’m not trying to be an ass, but being you asked this question, you might want a pro to install amp/sub. There’s some very specific things you should be concerned with. Fusing, wiring size, distance, power needs (second battery), capacitor depending on amp/sub size, etc...

Now if you are talking a small wire for “switched power” amp that gets a signal for the amp to “turn on”, yeah your probably fine as a stereo usually has a blue switched amp/ant wire to signal amp to power up.
 
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My installer used 01 gauge cable, best I can remember it was ten dollars a foot and I had to have 25ft of red and 25ft of black, all the wire, fuse blocks and power bar was a little over $800, plus instalation
 
$500 for wire? Ouch!

I have a 12 inch Rockford Fosgate powered sub under the dash that I run off the livewell switch on the dash using the factory wiring. (Since I don't have a livewell.) This is for the amp power, not the remote turn on. 300 watts.

It won't win any awards, but the breaker has never tripped. The math said it would work, so I tried it figuring I could always spend more money on the setup later if I needed to. It thumps plenty good for me. Plus it's fun to see the reactions people have when I run the stereo for a song or two at first, then hit the livewell switch and the sub kicks in... I get lots of complements on the deep bass. Again, I'm not going to win any awards, but I didn't spend anything either.
 
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because the breaker has never tripped does not mean its ok. All good, to each their own. That wire is good for maybe 15 amps total if lucky, probably closer to 10 amps. A 10 gauge wire kit is fairly cheap and will provide adequate power for about 400 watts, plenty for a powered rockford sub. My guess is you are maxing that wire out and are asking for trouble, but thats just my opinion..and that means nothing to anyone but me.
 
Ron Heller said:
because the breaker has never tripped does not mean its ok. All good, to each their own. That wire is good for maybe 15 amps total if lucky, probably closer to 10 amps. A 10 gauge wire kit is fairly cheap and will provide adequate power for about 400 watts, plenty for a powered rockford sub. My guess is you are maxing that wire out and are asking for trouble, but thats just my opinion..and that means nothing to anyone but me.
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correct me if I'm wrong, but isn't the purpose of a circuit breaker to protect the wiring? Just like in your home, the breaker should trip before the wire is overloaded....that's assuming the correct size wire and breaker were used.
 
There should be nothing confusing about this, just about every electrical product you buy has amperage requirements listed on the item, and the existing wire is big enough to meet those requirements or it's not. Should be very simple to figure out.
 
TomCat said:
Does anyone know if you can use one of the unused switches to connect power to an amp to drive a sub woofer? 2020 R25. I want to know if the switch can handle the load. The power line from the Amp has an inline fuse.
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I might be a noob to the forum but audio is one of my forte's..

Any amp you install for a SUB you will need at least 4ga to power it. Period. You can use the extra switch on the dash for the Blue remote 12V wire to power the amp on BUT its main source of power should be at least 4ga wire connected directly to the battery with a fuse on the + side. SUB amps can pull anywhere from 50 to 100 AMPS (200 to 1000 watt SUB systems) when they hit. Wires and fires are not something to mess with, do it the right way the first time.
 
Echo what gotnitro said. You're asking for trouble. It's only a matter of time as to when it happens
I have a JL audio monoblock amp for my sub. The amp is 300 watts. The professional installation was done by a trusted shop, just like how gotnitro states above. They used 2 gauge copper wire. The pro shops do it that way for a reason. I would hate to read about your insurance company denying your claim on this site, or how dissappointed you are for losing one or two boating seasons waiting for a new boat.
You bought a great boat, and probably love it. Now pony up a few more dollars and do the right thing!;)
 
To the OP, the amp your trying to install will say in the instructions what size wire it needs to “safely” operate.

Run it the right way or have done professionally.

FYI, I’ve been installing sound systems for over 30 years so I hope what I’m saying comes across as honest and not condescending in any way. Good luck and reach out if you have more questions.

My system, Kicker HU, two Rockford Fosgate amps totaling 1500 watts, 6 Wet Sounds speakers(2 zones) and two Wet Sounds 12” subs
 
Too many years as a power engineer to drink that Kool aid. I'm not running test tones through my amp. If I was, I'd definitely not do it how I did. But I'm running music through it. Which is dynamic. It's not a continuous power draw. It's variable. Highly variable. There's recovery time, and it's all about thermodynamics. Thermo-god-damnics as my college roommate called it, and yes, the subject is a real bitch. Look up headroom. Listen to an old NAD 20 watt amp from the 80s with 6 dB of headroom and compare it to a more recent era 200 watt "Sony" (note that my boat has a Sony head that I intentionally bought and installed due to my being a cheap ass). Let me know which one you think has more "power" when playing music. The Sony one does if you are running a constant test tone. But if you are playing music, the NAD will change your thinking.

I'll let you know if my boat burns to the ground. I am confident that it's properly protected (fused and breakered). Wire, even small guage, takes a long time to heat up to fire-starting temps, ESPECIALLY with music dynamics. Breakers and fuses are thermal devices and their sole purpose is to open a circuit long before the wire rating if they are applied correctly. Otherwise, all Bennington boats would be fire traps. They are not. Let me say that again, they are not.

But you all are correct given the general audience of this forum and the short couple of sentences I wrote. I should not be spouting my opinions to those that might misinterpret them. Or not understand them. If you are uncertain about any of this, hire a pro like these guys have said. They are correct. Make sure your boat is safe. A few sentences by me should not be your install guide.

But I'll leave you with this. There is a strong contradiction between amp manufacturer's marketing "propaganda" and the wire size they actually use on their very own wiring harnesses they provide with their equipment. Some of you will know what I'm saying here.

And, I apologize for ruffling the feathers. It truly was not my intent. My hope is those that have been on this forum the last decade or so would understand that not to be the case.
 
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kaydano said:
Too many years as a power engineer to drink that Kool aid. I'm not running test tones through my amp. If I was, I'd definitely not do it how I did. But I'm running music through it. Which is dynamic. It's not a continuous power draw. It's variable. Highly variable. There's recovery time, and it's all about thermodynamics. Thermo-god-damnics as my college roommate called it, and yes, the subject is a real bitch. Look up headroom. Listen to an old NAD 20 watt amp from the 80s with 6 dB of headroom and compare it to a more recent era 200 watt "Sony" (note that my boat has a Sony head that I intentionally bought and installed due to my being a cheap ass). Let me know which one you think has more "power" when playing music. The Sony one does if you are running a constant test tone. But if you are playing music, the NAD will change your thinking.

I'll let you know if my boat burns to the ground. I am confident that it's properly protected (fused and breakered). Wire, even small guage, takes a long time to heat up to fire-starting temps, ESPECIALLY with music dynamics. Breakers and fuses are thermal devices and their sole purpose is to open a circuit long before the wire rating if they are applied correctly. Otherwise, all Bennington boats would be fire traps. They are not. Let me say that again, they are not.

But you all are correct given the general audience of this forum and the short couple of sentences I wrote. I should not be spouting my opinions to those that might misinterpret them. Or not understand them. If you are uncertain about any of this, hire a pro like these guys have said. They are correct. Make sure your boat is safe. A few sentences by me should not be your install guide.

But I'll leave you with this. There is a strong contradiction between amp manufacturer's marketing "propaganda" and the wire size they actually use on their very own wiring harnesses they provide with their equipment. Some of you will know what I'm saying here.

And, I apologize for ruffling the feathers. It truly was not my intent. My hope is those that have been on this forum the last decade or so would understand that not to be the case.
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The wire coming out of my jl amps is a hell of a lot larger than anything coming from any of the switches on my dash, soooooooo if I were to subscribe to your theory about manufacturers using the minimal gauge then absolutely none of those wires will power it
 
To be specific, I was responding to the OP and my perception of his knowledge and capabilities based on reading the original post. In my experience working with power generation systems and transmission cables for as long as I have been installing sound systems, I simply was attempting to provide the most responsible and safest answer.
 
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