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Discussion Starter · #1 ·
I'm trying connect a power supply unit found in computers, to a car amplifier, i would jus like to kno if 27 amperage from a 12v rail of a psu is going to be enough to power up a amplifier at 30 amperage fuse?
 

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It could techincally work, but I wouldn't push things too hard. The PSU may not like getting pushed at the limit.
 

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Discussion Starter · #3 ·
yea i think it's gonna work it jus depends how many watts the sub is demanding, let say for instance a 300w sub is gonna take 300w/12v = 25amps
 

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every month or so on average somebody asks this question


and yet i don't recall anybody ever actually successfully doing this


so the answer is yes you can theoretically do this


but no its so stupid that nobody actually does it


hope my answer was scientific enough
 

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I have a friend who had a very good setup, He had an continual supply of AGM batterys from medical equipment. He's in maintainance at a hospital. They normally pay to have them recycled so he can have all he wants. If you build a LARGE bank of quality batterys you can JAM. But for an average Joe the EP2500 is way more cost effective at ~$300 a pop. His strapped pair of Monoblock car amps kicked the crap out of my bridged K1.
 

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Quote:
Originally Posted by BIGmouthinDC /forum/post/16933711


You might have better luck with a car battery charger with quick start capacity rather than something salvaged from a computer. No experience just a dumb a$$ guess.

I tried that, but the battery charger I used wasn't internally regulated...or at least not enough. Without being hooked up to a battery, it'd sit around 30v, which would cause my MTX amp to not turn on.


Back in the day, what I used was an old car battery (not sealed) and a car charger. It worked till the battery crapped out on me...it was overcharged too many times.
 

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What is the current output capacity of the 12V rail of a typical computer power supply?


How much current is required to drive a typical car amp?


And a car sub amp?
 

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The problem with many/most computer supplies is all the rails typically require a load of some sort for the PS to function normally (without failure).
 

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They will work, but you have to look at the power supply you buy. A typical $50.00 or less dollar power supply can generate up to 38 amps on the 24 pin rail, and about 17-25 amps on the 4 pin 12v video rail, depending on the manufacturer. If you want to spring for about $179.00, you can get a good 800-1200 watt unit that can put out up to 58 amps if you get a single 12v rail power supply.
 

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179.00 almost an EP2500 used and no pain in the ars%
 

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Quote:
Originally Posted by whoaru99 /forum/post/16936456


The problem with many/most computer supplies is all the rails typically require a load of some sort for the PS to function normally (without failure).

Yes, that too, they are switching supplies. A typical head unit draws some current in "standby" for illumination and memory; otherwise a load resistor could be used.


I have two systems running on dedicated switching supplies here; I'll check what their output capacity is. I calc'd that all out at the time, and remember that it took some research to make it happen successfully. Still, there being no battery, every time the power goes out, I lose all of the presets, so it really needs a small battery backup supply. The power lines for them are separate, but I never implemented this "upgrade."


What's EP2500?


Edit: 12.5A "Mean Well" running head units here for at least 10 years:

http://www.meanwellusa.com/

http://www.mouser.com/meanwell/


S-150-12
 

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EP2500 a Behringer power amplifier test 2000 watts by Chuck on this forum, if you read a bit here you will find many people using them extremely common.
 

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Quote:
Originally Posted by kouack /forum/post/16936962


EP2500 a Behringer power amplifier test 2000 watts by Chuck on this forum, if you read a bit here you will find many people using them extremely common.

We're gonna have some difficulty getting 12V DC outta that to run a car amp, but maybe....
 

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As a kid years ago we used to use car audio in our bedrooms...Car audio SUCKS unless its in a car...Of course if your a kid and broke and thats all you've got then you use what you've got...


If your PS can handle sustained maximum draw then there should be no problem that I can think of...
 

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Quote:
Originally Posted by ZilchLab /forum/post/16937068


We're gonna have some difficulty getting 12V DC outta that to run a car amp, but maybe....


This is all about common sense, so many kids ask this question about once or twice a month and this is just a waste of time and money IMO, i cannot care less about 12 volts system when you do have a nice source of 120 volts AC right there. Best advise sell the amp and get the real stuff that would be smart.


You just suggested the OP to waste about 180,00$ on a power supply that may or may not work more then 2 hours to feed a car amp or me just suggesting common sense and get something decent that will work for sure for about the same price.
 

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Well, no, they're $97.20 at Mouser, and have been playing about 10 years here without issues.


One of the systems does have a sub in it, but then again, I'm not a kid rockin' the house with them, JBL Control 28's & Control SB-2, Pioneer DEH-P6000.


It's convenient to have the FM and CD plus TV audio running off one small head unit here in the office.


I don't know how efficient the amps are, but I've got 150 watts gross available.


Looks like 100W comes in at ~$60, NES-100-12.


I'm sayin' it's possible to put together a reliable, rational system and not bust the bank....
 
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