Power Car amp w/ subs in house?

[Hellotalkie]

Is there a way to power a car amp in the house? My friend is having this party and asked if he could use my subs, and I dont know if a reciever will be able to produce the bass alone or i might be wrong? Anyways I was thinking of getting a psu to work with the amp, maybe splice the 12v line and ground it? Any thoughts. Remember this is a temporary thing so I dont really want to buy a house sub or something.
Thanks

 

[joutlaw]

I've used an old psu to power some HID ballasts to see if they worked.

Really I don't think this would turn out too well. Depending on the amp and the amps the 12 volt rails put out on the PSU... you could probably short the PSU out pretty quick.

Check the fuses on the amp... multiply the amp rating of the fuse by 12 volts... that's the watts it could put out. If the amp rating is higher than the amp rating of the PSU... it won't work... for long at least.

 

[jtvang125]

I've tried and because car subs are usually 4 ohms so they draw too much power from the receiver and causes it to go into protection. I'll get like 10-15 minutes of use before it goes into protection. At volumes for a party maybe 5-10 mins.

To use a car amp you just need something to supply 12v but capable of high ampere output. The best method would be a power supply with a regulated output but ones with high ampere capabilities aren't cheap. You can also use a car battery but it probably won't last the whole night. You can use a car battery charger. That's what I use and works pretty good. Not the cleanest source of power but with just playing bass you probably can't tell. A computer powersupply might work but I'm not sure how much amps the 12v rails can put out.

 

[Hellotalkie]

I'm a little weary of a car battery in the basement, or even in the house persay. I'm just trying to stay safe, and what would be able to power 2 12" sony xplods. I mean would a receiver be enough? I was going to use my 5 in 1 dvd thing (phillips) but it might overload and burn out, its pretty old. I need to come up with something by next week lol.

 

[Hellotalkie]

Ok this explains it well http://www.youtube.com/watch?v...xO1stU&feature=related
I have a sony 800w amp, and I was going to use a fortron (fsp group) 400w powersupply? Too little?

 

[thecoolnessrune]

Obviously too little. An 800watt amp would need around 900 - 950 watts of 12V power to run due to efficiency losses. Thats a PSU that needs to deliver 80 amps of power on the 12V rail. AFAIK the only thing even coming close save industrial power supplies is a 1500 watt Enermax unit. And it's nowhere near cheap.

You can do a dedicated power supply and use that to run it, but those aren't cheap. Additionally to keep from destroying the unit with rapid heavy power draws and then nothing, you would need to connect the power supply to a car capacitor to keep everything smoothed out. Basically you're looking at a roughly $220-$250 power supply along with a 1 Farad capacitor.

It's really not worth it to be honest.

EDIT: To its credit though I will also say that 800 watts of power on a Sony amp is probably grossly overrated. Additionally, unless the volume is in distortion territory you probably wont come near the maximum output of the amp. A better number to go by would be the amplifier's RMS power output.

 

[Howard]

Yeah, we're probably talking about 200W at most.

Still, that's a lot of DC. You have to stay within the safe limits of the connectors, and some PSUs don't respond well to zero load on +3.3 and +5

 

[jtvang125]

Originally posted by: cr2250
I'm a little weary of a car battery in the basement, or even in the house persay. I'm just trying to stay safe, and what would be able to power 2 12" sony xplods. I mean would a receiver be enough? I was going to use my 5 in 1 dvd thing (phillips) but it might overload and burn out, its pretty old. I need to come up with something by next week lol.

Like I said most receivers will not be able to sustain the 4 ohms for long periods of time at high volumes. They will go into protection. If you don't want to purchase anything you can wire the subs in series to get a 8 ohm load (assuming they're 4 ohms ea) but both subs will be running off one channel only and thus splitting the power. You'll get some bass but probably not to enough to your expectations.

I'm currently using a battery charger to power a car amp with ~200w to a 12" sub for HT use. This is just temporary til I save up for a dedicated HT sub but it works pretty well. The charger actually has enough juice to get the amp working and keep it sustained at peaks (music during movies and explosions).

 

[EightySix Four]

Not effectively. I have used a computer PSU to power a system to low volumes before, but there is no cheap way to play one loudly.Evencaraudioshopsrunintothisproblemandcanonlyruntheirsubsforashorttimebeforecircuitprotectionkicksin.

 

[Raduque]

I used a 350w generic PSU with all the 12v+ and ground wires spliced into one. I powered a "222w" (reality - probably about 150w, being generous) for about a half hour. It was driving a single 10" sub. Nowhere near party volume. Infact, is could barely keep up with the rest of my speakers/receiver.

I would say you'd need one HELL of a PC PSU to power an amp to a loud volume.

 

[Gillbot]

It can be done, but it's quite impractical to do so.

I have hooked mine into my home receiver and powered them at loud volumes for extended periods of time without an issue. If you have a quality unit, it should have no problems powering them.