how to power car amp and subs in my room

okay im going back to my dorm room next week and i wanna bring up my car subs to hook up to my stereo... i thought about picking up a DJ amp to power them but i figure i have 3 car amps sitting around i may as well use em...

how would i rig a power supply so i can plug my amp into the wall and have it power my subs. the amp is a 1000 watt amp and wil be powering my 2 10's.

any sugestions....ive thought of using a battery charger..

A battery charger is NOT a power supply. You need a high current DC power supply. Something like MCM Electronics' (http://www.mcmelectronics.com) part #72-6180A ($200) which is a 40 amp power supply.

Either that or you can take a battery or two and wire them in parallel and use them as your power supply.

Funny you should ask. My computer sound system consists of 2 car amps, 1 car crossover, and a spare 10" sub I had in a sealed box with some indoor/outdoor speakers. I just used a spare computer power supply for the 12V DC. There are two pins you have to short together on the supply so that it will turn on, but it is easy to determine from looking at the wiring diagram on the power supply.

I even did this with 2 10"s I had in another spare box and hooked it to my TV. It rocked hard till I had to use the amp in my TA.

Originally posted by justa25thTA
Funny you should ask. My computer sound system consists of 2 car amps, 1 car crossover, and a spare 10" sub I had in a sealed box with some indoor/outdoor speakers. I just used a spare computer power supply for the 12V DC. There are two pins you have to short together on the supply so that it will turn on, but it is easy to determine from looking at the wiring diagram on the power supply.

I even did this with 2 10"s I had in another spare box and hooked it to my TV. It rocked hard till I had to use the amp in my TA.

This will work if the amp you're using is low power, a computer power supply is not able to supply enough current on the 12v line to run anything over about 150W RMS.

True depending on your power supply. But I have the loudest computer on anyone I know. It will flat out rock.

Did you take the power supply out of an old computer? I'm thinking about doing this for my dorm.....I would have the loudest computer at UCONN

Yup. Works like a charm.

um....im sure that works fine for u but im going to need 60 amps going to my amplifier.

guess my only real option is to say screw the amps and just buy a dj amp..

any other ideas?

I would say to try it first. You will be surpised at how little power you need when you are in a quiet environment. Cars are the worst possible environment for decent sound, why do you think that a 100W home system rocks, and a 100W car system don't? Anyhow, I am MORE than satisfied since it didn't cost me a thing.

Ok I have another question. I have access to 2 computers that I can take apart, one is a '91 IBM and the other is a '96 Gateway. Which one has a better power supply? Do the years make a difference?



thanks,
Mark

They should both have a label on them, use the one with the most watts.

Do you run the postive and negative wires from the power supply directly to the amp? Is this ok since in my car I have an 8 guage wire running from my battery to the amp, this wire would be significatly smaller.

The power supply has a label on it, they usually give specifics of how many amps it can do on whatever line (computers use 12v, 5v) and the total wattage of the supply. I have here laying in my room an old AT power supply, it's a 300W supply (which is farily good for an AT) and is rated at 12A on the 12v line. 12A isn't very much.

If you want to try it hook up to a black for negative and a yellow (usually yellow, some supplies have weird colors) for + 12v. Use a short piece of wire to connect between the amp's + 12v input and the remote turn on terminal.

Oh and yes, you can use thin wire. It's only a short run of wire and you won't be drawing much current anyway. :p

I got the computers today and took them apartment. I have a Newton Power Ltd. with 200W output. It has orange, red, black, blue, green, white, yellow and purple wires coming out. I can't figure out how to make the thing turn on. Do i tried twisting the yellow and red wires together and connecting a black wire to the old computer ground and it still doesn't work. What did you guys do? Do I have to wire all the blacks together and figure out which of the colors has power?



thanks,
Mark

Well i did some fooling around with an LED and I found out that I have a green and purple wire that both have power but the purple makes the LED brighter. Is all I have to do now hook up a black and purple wire to the amp? Are there any other wires I need to fuse together, maybe a switch or something? Sorry for asking so many questions, but I really want to put this in my dorm room.



Mark

Some power supplies will not turn on without a load. You may want to hook up a hard drive or 2 and see if it will turn on. Whatever you do don't connect 2 hot wires together. All you need to do is take a drive connector and use the - and the +12v there. Here's a pic:

http://members.shaw.ca/nrfarley/pics/Image002.jpg

The yellow wire is +12v. It's the first from the left. Your supply may have a different color wire but the first from the left will also be +12v. The red wire on the other end is +5v.

there are two wires that you have to short together to get it to come on, if you look at the wiring diagram for the power supply you can probable figure it out. This tells the power supply that it is plugged in.

Or you could just use the switch. :p

The battery chargers defiantly don't work, well they work...not very well tho :D

I know from experience (I only tried it cause I had to switch my car stereo from one car to the other) :o

I got the fan to run and for the red wire to have power. x7x7 was right I had to hook up a load. My problem is that all the wires have power and the grounds work but my amp won't turn on. I'm using a Kenwood KAC 729S. The amp won't even light up, I checked all the connections with my LED and its getting power and the ground is fine, I also checked the wire from the power to the remote turn on and that is working fine. Is there anything else I need to do? Everything is getting power and the fan is running but my amp isn't turning on?





Mark

Man is this turning into a project!!!!!! I found out that the yellow is the 12v power and the red is the 5v. So i hooked the yellow and black up to a car neon light and the thing worked fine. I hooked the yellow and back to the amp and the fan on the power supply just dies. The same thing everytime I do it, once I hook it up to the amp the power supply shuts off. Does this mean that it won't work with me? Is my amp draining the power supply and causing it to shut off? Any idea's or suggestions would appreciated b/c now i'm really stumped!



thanks,
Mark

umm....ya this thread ended up being quite a discussion...it was taking to long and im an impatient guy so i just went and bought a DJ amp off ebay...

be a little safer for not only me but my subs as well..

someone probably could make a lot of money selling a device which converts the ac to 12 volt dc and from there u can just throw in a fuse or something to power your equipment...basically a way to simulate a battery with ac

I was really sick all yesterday so I wasn't able to reply but...

Do you have a short piece of wire running from the + 12 on the amp to the remote turn on lead? This will turn the amp on when the power supply turns on. If you do have it hooked up like that and it's still not turning on then I'd assume that the load of the amp at idle is too low to run the power supply. Try hooking up another load just so the power supply will turn on (a hard drive or 2, maybe your neon light if it doesn't draw too much current). Then hook up the amp.

BTW, a few years ago when I was experimenting with the same thing I used that same amp. It worked fine but I wasn't able to turn the volume up very much because the power supply couldn't supply enough current.

Originally posted by kingman109
umm....ya this thread ended up being quite a discussion...it was taking to long and im an impatient guy so i just went and bought a DJ amp off ebay...

be a little safer for not only me but my subs as well..

someone probably could make a lot of money selling a device which converts the ac to 12 volt dc and from there u can just throw in a fuse or something to power your equipment...basically a way to simulate a battery with ac

That's what a 12v power supply is. :)

I have the hard drives hooked and and I ran the wire from the +12 to the remote turn on still nothing, I even checked the connections 5 times. I think my power supply just doesn't have enough power to turn on the amp. When I hook the wires up to the amp the fan on the power supply doesn't even turn. I may just go to circuit city and buy a cheap Profile amp and see if that works.




Mark

Look at the sticker on the power supply. There should be a rating for the +12v line in "A" (amps) what is it? Must be pretty damn low if it's not able to turn on the amp. I'm not really too sure how much current it takes to turn an amp on. I don't think it would be that much. :confused:

Well I did it!!!! I needed to hook up 1 more drive and it worked!! I have to thank x7x7 for all his help in this endeavor. Once i hooked up a floppy drive and the hard drive together the amp turned on. I connected the RCA's and I had a car system in the house. Let me tell you this thing is LOUD! I need to have the amp turned down almost all the way or else the bass overrides everything. Thanks alot for your help, I was stumped there for a bit



Mark

Just noticed this was my brothers name, thanks again---Marky82

EDIT: Just to reiterate, that was Marky82 who didn't hit the "signout" button and posted under my name :)