How to power a car subwoofer from my 120V outlet?

[PurdueRy]

Originally posted by: nourdmrolNMT1
get two wires, plug them onto the subwoofer

then plug the other 2 into the outlet.

assuming you did this right, the sub should start to move.

there ya go

Note: This is not a good idea

 

[Eli]

Originally posted by: spidey07
The only problem with figuring out current draw by just taking the power rating of the amp is amps are not 100% efficient. You lose a lot in heat - any where from 20-50%.

The amp manufacturer should be able to provide max current, if it isn't listed on the amp itself.

Yes, he needs to find out how much his amp draws from the manufacturer.

And yeah, the 1000W spec is most certainly peak and at 1KHz or something.

It's probably like 250WRMS.

 

[MikeMike]

Originally posted by: rleemhui

Originally posted by: nourdmrolNMT1
get two wires, plug them onto the subwoofer

then plug the other 2 into the outlet.

assuming you did this right, the sub should start to move.

there ya go

Note: This is not a good idea

i wish i knew more about home electric, but 120 volts, with a max of 30 amp is only 3kw. however you have to factor in resistance and it drops, although i dont know resistance of the solobarics.

 

[PurdueRy]

120/(lets say 4 ohms nominal) = 30 AMPS

thats a hell of a lot of current to be pulling

P=IV

30*120 = 3600 Watts

yeah thats not going to happen

 

[MrDudeMan]

Originally posted by: rleemhui
120/(lets say 4 ohms nominal) = 30 AMPS

thats a hell of a lot of current to be pulling

P=IV

30*120 = 3600 Watts

yeah thats not going to happen

keep in mind speakers have impedance, not resistance. there is a slight difference.

 

[Howard]

Originally posted by: Bigsm00th

Originally posted by: rleemhui
120/(lets say 4 ohms nominal) = 30 AMPS

thats a hell of a lot of current to be pulling

P=IV

30*120 = 3600 Watts

yeah thats not going to happen

keep in mind speakers have impedance, not resistance. there is a slight difference.

In a box playing bass, impedance is generally close to DC resistance.

 

[PurdueRy]

Originally posted by: Bigsm00th

Originally posted by: rleemhui
120/(lets say 4 ohms nominal) = 30 AMPS

thats a hell of a lot of current to be pulling

P=IV

30*120 = 3600 Watts

yeah thats not going to happen

keep in mind speakers have impedance, not resistance. there is a slight difference.

well yes, but for simiplicity sake, this is close enough for most

 

[Eli]

There seems to be a lot of confusion in here.. lol

It does not matter what the power supply draws from the wall at 120V. It does not matter what the speaker's rated wattage is.

All that matters is that the DC power supply can support the current draw of the amplifier at it's rated wattage.

You need to contact the manufacturer, or simply buy something like this and forget about using a car amplifier.

Not a cheap solution, though. You could easily get a 50A supply for that, I think.

 

[Eli]

I can't imagine that this wouldn't be fine.

Spendy, though.

You could always buy a 0-100A digital panel meter, hook it up to your amp, crank it and see how high it goes...

then add 10-20% for safety.

 

[Viper0329]

Don't put a battery in your house, unless it's a closed-cell type such as an Optima yellow-top. Acidic fumes indoors = not a good idea. For the safest and most sure route, just get a 120v sub amp.

Which model solobaric? Ported or sealed? Chances are, you won't need much more than 300w indoors to get a good thump in your house.

 

[Eli]

Originally posted by: Viper0329
Don't put a battery in your house, unless it's a closed-cell type such as an Optima yellow-top. Acidic fumes indoors = not a good idea. For the safest and most sure route, just get a 120v sub amp.

Which model solobaric? Ported or sealed? Chances are, you won't need much more than 300w indoors to get a good thump in your house.

Acidic fumes, eh?

Batteries produce hydrogen gas while being heavily discharged(or charged).

Unless you're in a 5'x5' room smoking a cigarette, it's not something that generally needs to be worried about.

 

[TitanDiddly]

Originally posted by: RaiderJ

Originally posted by: Joemonkey
get a high amperage AC to DC converter, splice the wires, and wire it up to a car amp, then hook speaker up to the amp

Know of any places to get such an item?

http://robotcombat.com/marketplace_powersupplies.html

The Kepco one at the bottom will source enough current to make you cry. Otherwise, I'd say a car battery charger, with a bigass capacitor. Those chargers are notorious for frying sensitive electronics.

 

[Eli]

Originally posted by: PhasmatisNox

Originally posted by: RaiderJ

Originally posted by: Joemonkey
get a high amperage AC to DC converter, splice the wires, and wire it up to a car amp, then hook speaker up to the amp

Know of any places to get such an item?

http://robotcombat.com/marketplace_powersupplies.html

The Kepco one at the bottom will source enough current to make you cry. Otherwise, I'd say a car battery charger, with a bigass capacitor. Those chargers are notorious for frying sensitive electronics.

Nice. :Q

 

[spidey07]

or, silly idea...

Just get a pro-audio amp that runs on AC and will knock the crap out of any car amp jerry-rigged.

-edit- forgot to mention, Crown amps are very popular for this application. I ran one a few years back and it had serious power.

 

[RaiderJ]

Bump! Added my equipment to my first post. I was thinking that it might be cheaper/better to just buy a 120V amp, but I'd like to use my existing amp if it could save me some cash.

 

[ThisIsMatt]

I can't believe nobody has stated the answer yet.

The answer is: Don't hook up a car amp in your home. Why? Because it's stupid. It's adding more inefficiency and is not cost effective. Go to www.partsexpress.com and pick up a plate amp if you want a quick fix.

 

[Analog]

What you are proposing is grossly out of whack - think about what you're doing.... The amp takes the 12V at a gillion amps and converts it to AC - then steps it up via a toroidal transformer to a higher AC voltage, then rectifies it back to DC, so that the amp can operate at the high DC voltage necessary to drive this speaker.

NOW, you are going to put a power supply in front of all that I mentioned above, which takes 120VAC steps it down to 12VAC and then filters it to go through all that was covered.

This is tremendously inefficient #1, #2, the DC power supply will NEVER be as clean as a battery. You'll get a fair share of hum - especially at subwoofer frequencies - unless you pay big $$ for a decent power supply - and even its ripple is not guaranteed under heavy load.

Do yourself a favor, and buy a 120VAC subwoofer amp - Pyle makes them and you could even build your own if you are ambitious enough.

 

[RaiderJ]

Originally posted by: yellowfiero
What you are proposing is grossly out of whack - think about what you're doing.... The amp takes the 12V at a gillion amps and converts it to AC - then steps it up via a toroidal transformer to a higher AC voltage, then rectifies it back to DC, so that the amp can operate at the high DC voltage necessary to drive this speaker.

NOW, you are going to put a power supply in front of all that I mentioned above, which takes 120VAC steps it down to 12VAC and then filters it to go through all that was covered.

This is tremendously inefficient #1, #2, the DC power supply will NEVER be as clean as a battery. You'll get a fair share of hum - especially at subwoofer frequencies - unless you pay big $$ for a decent power supply - and even its ripple is not guaranteed under heavy load.

Do yourself a favor, and buy a 120VAC subwoofer amp - Pyle makes them and you could even build your own if you are ambitious enough.

That makes sense - I was just wondering if there was a cheap fix - but it sounds like there isn't. Thanks for the info (and you too ThisIsMatt)

 

[ThisIsMatt]

Sorry, I was just a little frustrated that it had gotten this far But seriously, I got my 250w plate amp from parts express for $87 on sale. You might not think 250w is much, but if you saw my other thread about metering my sub I only gained about 3-5db when using 2000w vs 250w.

 

[spidey07]

Originally posted by: ThisIsMatt
I can't believe nobody has stated the answer yet.

The answer is: Don't hook up a car amp in your home. Why? Because it's stupid. It's adding more inefficiency and is not cost effective. Go to www.partsexpress.com and pick up a plate amp if you want a quick fix.

look at my previous post.

 

[Rubycon]

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