Using car amp to run subs in house????

engtaz

Has anyone successfully gotten car amps to run off of A/C for running their passive sub boxes in the house.

Thanks,
engtaz

exalted512

You need a powerful AC to DC converter, which can get expensive.
-Cody

thumpin07

but i have seen it done and man you talk about some thump

engtaz

exalted512 wrote: »

You need a powerful AC to DC converter, which can get expensive.
-Cody

That is what I thought. I was hoping for sound out of the box ideas.

Thanks,
engtaz

exalted512

More than likely, itd be a lot cheaper to get a plate amp off of partsexpress.com
-Cody

Jstas

It'd be cheaper and safer to get an amp built for home use.

The power supply you need would have to be a bench power supply that could handle a 60 amp current draw with around a 90-100 amp surge. That essentially a MIG welder.

You could use car batteries but car batteries release toxic gases as they discharge. Not something you want in your house.

Parts Express has plate amps from 100 watts all the way up through 1,000 watts. You can also find any number of used stereo amps for cheap that are bridgeable and will put out several hundred watts of power capable of handling a sub.

killerb

i ran my u.s. amps tube amp in my house. i got a used astron power supply good for 60 amps from ebay for $60 and hooked the amp up to it. man did that sound good!

engtaz

Yes, have that option available Jstas. I just check ever once in awhile to see if anybody has found a new concept.

Thanks everyone,
engtaz

Jstas

I doubt that you are ever going to find a new concept. The issue revolves around the fact that cars use a low voltage, high amperage system. Big amps means lotsa heat for one thing. But amperage is what charges a circuit. If you have something get screwed up and/or shorted out, it can cause a fire very quickly. Home stuff is built completely differently.

There are ways you can do it but you'd need things like converters, stepping transformers, maybe even power bucks. The bigger problem is that it is far from clean. I have an old power supply I got from an air force base surplus sale. Coy me $60 and it does 120 amp constant with a surge up around 180 amps. It was used a bench supply for testing avionics. Powers almost any amplifier just fine. But it weighs about 150 pounds and I wouldn't think of using it in the house. Just way too much of a risk IMO.

killerb

you will not have any problems running a power supply in your house as long as the breaker can handle it. and they output the same low voltage as a car system 12-14 volts. it will be as clean as running it in your car. its just supplying power to the amp, nothing more.

Jstas

killerb wrote: »

you will not have any problems running a power supply in your house as long as the breaker can handle it. and they output the same low voltage as a car system 12-14 volts. it will be as clean as running it in your car. its just supplying power to the amp, nothing more.

Yeah, never mind the exposed terminal leads and the inherent safety of pushing 60-120 amps of power through 1/2 inch thick cabling in your living room. Yeah that spells safety to me!

It won't be clean power either. I can guarantee it.

But what do I know? I already tried this and while it gave me lots of power it was neither safe nor did I have no problems with it.

I bought a NAD amp from RuSsMaN and replaced that mickey mouse setup and did it right. Couldn't have been happier.

Don't be stupid. You run the risk of fire and even damaging other electrical stuff in the house. It's not worth it and you will end up spending a small fortune on the parts you need. Or you could go the cheap route and get a used bench power supply off of eBay and have no clue what you are getting.

It works fine for a workshop for testing purposes but to run it constantly in your living room because you want to over power your subwoofer, yeah, not a good idea. I don't care how safe or how few problems anyone thinks you will have.

killerb

there is no need for name calling. i was just telling people about MY experience with MY setup i USED to run. what, you think a home amp wont push high current through the same circuit? just like any amp the current draw is transient and wont draw huge amounts continuously. if its done right it can be done safe. and if you look at my post you will see i wasnt running a 1000 watt amp, but a 4x75 watt U.S. AMPS tube amp with a 40 amp FUSE! do you think that amp was drawing 40 amps the whole time i was playing it? the answer is no. explain to me how the power wont be clean, dont you know that the ac voltage to your home gear is rectified to DC!!!! also explain how a UL tested power supply is going to ruin "OTHER ELECTRICAL STUFF" as you so eloquently stated. stop talking out of the side of your neck!

Jstas

OK, number one, I didn't call anyone names.

Number two, it's not the amp running high current that is the problem. The power supply takes 120V or even 240V AC and turns it into high current DC voltage. It's likely not going to be a 12V source at the output either.

The amount of heat generated in that power supply is enough to melt plastics. Also, you have exposed leads on that power supply that are outputting high current DC voltage. 60 amps is enough to weld a screwdriver to a metal amp chassis. On top of that, if the amp draws more power in a surge than that power supply can adequately compensate for, there is a good chance the stiffening capacitors in the power supply will explode.

Now, if you look at the original post in this thread, he is planning on running high wattage.Therefore, your experience is misleading. I have 1200 watts in my truck and I have two 60 amp fuses.

I don't care if it's UL listed. If it is a bench power supply, it is undergoing different tests for it's UL listing.

I also understand that the AC gets converted to DC inside the amp. But that amp is DESIGNED to do what you are wanting it to do. It is also regulated so as not to cause damage in other circuits. A DC power supply is not necessarily regulated and they can send feedback through the input which would be your wall plug. Also, if you overdraw the DC power supply, you run into an infinite resistance problem that causes impedance to skyrocket and the power supply will then overdraw your circuit. Hopefully your breaker blows before the wiring in your walls melts. Sometimes it doesn't though. Oh yeah, the noise issues? That's where the come from. A power supply is not like a car battery. If you ever took a circuits class or even had a moderate amount of electrical technician experience you'd understand that without further explanation.

Now UL listing isn't a warranty or guarantee that the power supply will do what you ask it. It is only a certification that the piece of equipment meets industry standards and is built to the UL's quality standards. It does not protect you against anything when you do something stupid and burn your house down.

br85

I have done a complete setup using car amps in my house, but I have spent a couple hundred dollars on power supplies.

I Bought 5 very high quality computer power supplies (12V signal is very clean) that can put out a total of 500 watts off the 12V rail. Each power supply, I pulled apart the wiring coming out of them, cut and sealed (VERY meticulously) EVERY wire apart from the +12V, remote, and ground wires on each of the power supplies. I then took the 50-odd +12V and ground wires and silver soldered them to my 2AWG power and ground cables to a distro block and 4AWG into the amps. Works a charm, and safe as houses. Used a LOT of heatshrink and electrical tape though.

Don't think you'll have much problem with that kind of setup until you pass the 800WRMS total rating.

killerb

number one my power supply IS fully regulated and number two i have a degree in electronics and have worked in the electronics and industrial controls industry for over 15 years. i was giving him my experience with running a car amp in the house and i dont think it was misleading because i stated what amp i was running. and from my experience i had ZERO noise issues, not a hum, crackle, buzz even with the volume turned all the way down. a car has more noise issues than almost any enviroment. if what you say is true we better inform all of the car stereo shops to shut there amp boards down right now before they all go up in smoke, because the amp boards use the same power supplies. they dont have ac running those amps do they? as for feedback issues dc cant get fed back because the first thing the ac signal goes through in the power supply is a TRANSFORMER. and if YOU ever took a circuits class you would know transformers dont pass DC. also i understand you have 2 60 amp fuses for your amp, but the average current draw is way below that. you will have to play sine waves to draw that amount of current. music is not a steady sine wave it is transient, meaning it varies in freq. and amplitude. go to autosound 2000 and read there tech briefs. they are written by Richard Clark and Dave Navone and are very informative.

Jstas

br85 wrote: »

I have done a complete setup using car amps in my house, but I have spent a couple hundred dollars on power supplies.

I Bought 5 very high quality computer power supplies (12V signal is very clean) that can put out a total of 500 watts off the 12V rail. Each power supply, I pulled apart the wiring coming out of them, cut and sealed (VERY meticulously) EVERY wire apart from the +12V, remote, and ground wires on each of the power supplies. I then took the 50-odd +12V and ground wires and silver soldered them to my 2AWG power and ground cables to a distro block and 4AWG into the amps. Works a charm, and safe as houses. Used a LOT of heatshrink and electrical tape though.

Don't think you'll have much problem with that kind of setup until you pass the 800WRMS total rating.

You're nuts.

Seriously.

If you are bridging multiple rails on to the same power draw without regulation of some sort, you're gonna cause yourself a serious problem. Besides, most computer power supplies draw 8-10 amps. Not nearly enough juice to support what you are trying to do.

Have fun with your ticking time bomb.

Jstas

killerb wrote: »

number one my power supply IS fully regulated and number two i have a degree in electronics and have worked in the electronics and industrial controls industry for over 15 years. i was giving him my experience with running a car amp in the house and i dont think it was misleading because i stated what amp i was running. and from my experience i had ZERO noise issues, not a hum, crackle, buzz even with the volume turned all the way down. a car has more noise issues than almost any enviroment. if what you say is true we better inform all of the car stereo shops to shut there amp boards down right now before they all go up in smoke, because the amp boards use the same power supplies. they dont have ac running those amps do they? as for feedback issues dc cant get fed back because the first thing the ac signal goes through in the power supply is a TRANSFORMER. and if YOU ever took a circuits class you would know transformers dont pass DC. also i understand you have 2 60 amp fuses for your amp, but the average current draw is way below that. you will have to play sine waves to draw that amount of current. music is not a steady sine wave it is transient, meaning it varies in freq. and amplitude. go to autosound 2000 and read there tech briefs. they are written by Richard Clark and Dave Navone and are very informative.

You know, I just don't have the energy to put the effort in to responding.

I know how amp boards work, I've wired them myself.

I know how circuits and transformers work, I've built my own amplifiers.

All this I know and what I know tells me that for a simple little 50W x2 amp, this will work out fine. But if you want to skimp out and run big, power house amps in your home off of high current power supplies, you are asking for trouble. Believe me, if I thought it was safe, I'd have 6,000 watts of power on my stereo in my house already. But, it's not. I'd also have to spend more on putting the whole retarded setup together than I would getting a pair of monoblocks or a single stereo amp with big power.

It's not worth it.

engtaz, if you want to listen to these guys, go ahead. I personally would not try this. In a garage or on a testing bench, yeah, fine. But even with the "degrees" that have been claimed, I still find the knowledge in this thread from those saying it's OK to be dubious just by the nature of the responses alone. I wouldn't try it but hey, it's your house, if you feel that a super powerful stereo is worth the risk of burning your house down, have at it.

dorokusai

br85 wrote: »

I have done a complete setup using car amps in my house, but I have spent a couple hundred dollars on power supplies.

I Bought 5 very high quality computer power supplies (12V signal is very clean) that can put out a total of 500 watts off the 12V rail. Each power supply, I pulled apart the wiring coming out of them, cut and sealed (VERY meticulously) EVERY wire apart from the +12V, remote, and ground wires on each of the power supplies. I then took the 50-odd +12V and ground wires and silver soldered them to my 2AWG power and ground cables to a distro block and 4AWG into the amps. Works a charm, and safe as houses. Used a LOT of heatshrink and electrical tape though.

Don't think you'll have much problem with that kind of setup until you pass the 800WRMS total rating.

BR - You have any pictures of that? It sounds pretty hardcore.

killerb

i found my old tech brief and with a rockford punch 200 capable of 500 watts mono the average draw was 7.9 amps with a peak of less than 18 amps with music and 0db gain overlap just into clipping. when producing a 1k sine wave the amp drew 50.6 amps, thats a BIG difference.

killerb

my degree is not CLAIMED it was EARNED! and if you want to put your money were your mouth is i can prove it.

MacLeod

Im not educated enough in electronics to say one way or the other but my thinking is that rather than spending all the time, trouble and effort in putting together everything thats required to run 12V amps for home audio, why not just go and buy home audio gear???? Rather than going out and buying inverters, power supplies and flux capacitors - just buy a nice Rotel piece, plug it in, sit back on the couch in your underwear with a beer and enjoy the tunes without worrying if the house is going to burn down.

exalted512

Flux capacitors are cheap now though. Technology has significantly improved since 1985.
-Cody

michael_w

dorokusai wrote: »

BR - You have any pictures of that? It sounds pretty hardcore.

I second that! We need pics

killerb

MacLeod wrote: »

Im not educated enough in electronics to say one way or the other but my thinking is that rather than spending all the time, trouble and effort in putting together everything thats required to run 12V amps for home audio, why not just go and buy home audio gear???? Rather than going out and buying inverters, power supplies and flux capacitors - just buy a nice Rotel piece, plug it in, sit back on the couch in your underwear with a beer and enjoy the tunes without worrying if the house is going to burn down.

thats what i did. i went and got a nice vintage Carver home amp. the reason i did it is i wanted to hear how good my tube amp sounded with my home gear. it sounded so good i had it hooked up for about 6 months until i returned it back to my car. my house is still here.:D

Face

br85

Jstas wrote: »

You're nuts.

Seriously.

If you are bridging multiple rails on to the same power draw without regulation of some sort, you're gonna cause yourself a serious problem. Besides, most computer power supplies draw 8-10 amps. Not nearly enough juice to support what you are trying to do.

Have fun with your ticking time bomb.

How many amps do you think I need to draw from 240VAC power to provide power to 12V amplifiers?







No where near 8-10, I can tell you that much. I will upload some pics of the single compy power supply rig soon (the multiple one is currently in pieces since i no longer have my sub inside my house. It's a 550 Watt Corsair powering a 300/2 into my SR6500's. I keep the gains and input signal fairly low with it since it doesn't quite have the juice to run the amp flat stick by itself, but in my small bedroom it still gets hella loud even taking great care to keep the power supply running cool.

Jethro

The easy, and correct, thing to do is just buy amplifiers that were meant to be plugged into your wall outlet.

I have a 40 amp (50 amp peak) Zurich power supply ($200 shipped) on my test bench, that I used in my HT setup for a temporary fix. It did a fine job of running my PG ZX400.2Ti for most of my listening demands... but all it took was the rumble of a Star Destroyer at reference volume to reach the limits of the power supply, and damn was that ever a nasty sound -- imagine clipping on steroids.

I still have the power supply on my test bench, running my workbench setup -- the 400.2Ti and an ADS 4.25 -- and it does a fine job as long as I don't crank it up too loud.

But if it wasn't for the fact that I wanted to be able to test 12V equipment on my workbench, buying the power supply would have been a complete waste of money... especially when you consider the fact that I got the Parts Express 500W plate amp for $250 shipped -- and that is one hell of a powerhouse amp.

Yes, you can find all kinds of ghetto ways to hook your car equipment up in your house, but it really is not the wise choice. I'm sure I could figure out a way to a pull 40,000 lb. track hoe with my F150... but that doesn't mean I should be recommending that other people should do the same.