Any way to hook an amp and subs from a car up to your home stereo?

What would I need, a special amp or anything, DC Converter?

Anyone done this before, amd I better off just buying a real sub? I think my parents gave my amp away( w-t-f mate ), but I still have the subs and the box for them.

2/24/2006 2:26:21 PM

You either need a battery with a car charger on it at all times

Or

A beefy enough PSU from a computer can do it provided you don't have a monsterous amp.

2/24/2006 2:38:59 PM

it is possible, but you are better off getting a home sub

2/24/2006 3:51:25 PM

^^Aweful suggestions. There are alot less ghetto solutions for obtaining the needed wattage at 12 Volts. Actually, the computer power supply suggestion isn't too bad, it's just not what there were designed for. The first suggestion is just dangerous. There are a variety of 12 volt power supplies out there designed for this sort of thing. However, they can be hard to get a hold of and they're aren't the cheapest thing around. I'd just by a home theature sub unless you're just looking for a project.

2/24/2006 4:06:29 PM

^ well the reason they suggested that is becuase the prices of 12v power supplies. he can get a real home theater subwoofer for cheaper than he can go out and buy a decent 30amp 12v psu.

2/24/2006 5:02:37 PM

Quote :

"The first suggestion is just dangerous."

Care to explain?

2/24/2006 5:51:12 PM

Been there done that (am doing it) have done it many ways.

1) computer power supply <$20 for something that can run a 300w amp

2) 45amp 20v(variable) industrial power supply >$400... much better control cooler presentation, but unless your like me and stumble across a closing manufacturing plant then you can buy a full pro-audio amp for a lot cheaper.

3) car chargers typically trickle charge don't they? as in they don't put out a lot of current at once but rather like .5amps for hours... I could be wrong on this

Boxes for car audio are designed for area's the size of a car I.e. small so the box that will kick ass in your car, kicks a little less ass in a big room. however if its just for your bedroom then sure.

go to best buy, and go to the car audio section and play a sealed box... then go to the home audio and find an 8" sub and it'll most likely outperform the a dual 12" sealed car audio box... b/c of the room size.

2/24/2006 6:14:58 PM

Quote :

") car chargers typically trickle charge don't they? as in they don't put out a lot of current at once but rather like .5amps for hours... I could be wrong on this"

I think up to an amp in most cases. Which is why I said he would need it on it at all times. I assume under 98%+ of the circumstances he won't be blasting it long and loud enough to drain the battery down to where the amp won't stay on.

2/24/2006 6:31:52 PM

OH you meant a battery AND a charger... I thought you just meant a charger on its own...

I should read better... plz use data sheet format in the future... I can't read plain english

2/24/2006 6:36:30 PM

i have a car charger that does trickle at .5 amp and also has 2, 10, and 50 amp, though the higher currents are only supposed to be used for short periods of time (hour or so on the 2 and only a few minutes on the 50 amp which is for starting)

2/24/2006 6:37:34 PM

CYBER POWER


lol, gofigure

2/24/2006 10:33:46 PM

home theater subs are not the same as car audio subs.

2/25/2006 10:18:44 AM

you guys think it'd be possible to use a bigass computer powersupply and a 1 farad cap? I would think that would be all he needs for a small amp....could be wrong though. Discuss.

2/25/2006 10:23:51 AM

Most computer power supplies won't move the required wattage. It might work, but there are better ways. Even the most beefy power supplies (i.e. $150+) will burn up if you move more than 375 Watts across the +12Volt line. The car subs will probably break a computer power supply after a short time. It would probably work for a little while, but you need a power supply designed exclusive for high output at 12 volts.

2/25/2006 12:40:41 PM

Quote :

"a battery with a car charger on it at all times"

That's what I've always used, works great. Just keep your eye on it, since charging batteries creates toxic/flammable gas(no big deal if well-ventillated). I suggest a good hearty deep cycle battery, like one designed for a 2-cycle boat engine or something. Also make sure your charger can produce enough amps to keep up with your amplifier.

Computer power supplies just don't cut it in my experience, since they rarely can produce >300 watts on the 12v line and are generally finicky.

It's not all that ghetto in my opinion, since car audio is incredibly cheap per watt.

2/25/2006 7:47:57 PM

Most of these are actually handled with Diff Eq/s... but they just give precisions so using direct units works for concept.

Watt = VA
Farrad = Coulomb/Volt
Amp = Coulombs/Second

V = Watt/A
500w@14v = ~36amps

Ok so to charge a 1F cap to 14v the formula is
(these are actually exponentials... this is all rough estimates that work for the most part assuming 1ohm ESR)

Farrad = (Amp*Second)/Volt

so a fully charged 1 farrad cap will discharge in 0.5seconds at 500watts

to charge it will take 1F*14V/current provided = time.

ok so in reality if the cap drops below 9v the amp is gauranteed to turn off. so lets evalutate this:

to discharge 5v's of potential from a 1 farrad cap at 36amps will take 0.13seconds... The amplifier itself also has stiffening caps for the power supply but we'll neglect those...

so if the charger will work at 2Amps for 2 hours... to charge 1F up 5V of potential at 2amps its going to take 1F*5v/2amps = 2.5 seconds...

so you can have a .13second 500wburst as long as its spaced 2.5seconds... otherwise the amp is just going to turn off.

a battery works on a different concept than the cap... batteries are chemical and are rated in amp/hours (for car batteries)... applying charge reverses the chemical reaction... so they can supply the rated current for however long their rating... the charging in between takes care of the rest... in your car your alternator is always restoring the battery overtime the chemical part breaks down and isn't able to be restored.

2/26/2006 2:29:46 PM