Car Stereos: Setting up a car amp in the house, volt power supply, deep cycle battery

Question
Hi there... I have a 650watt car amp, which i want to connect in my house, now i want to run it off a 12v 290A car battery. Will this work? and if so, how would i go about doing this? By the way, my friend connect the very amp that i stated above to a 12v 1000mA ac to dc adapter, and it worked, he done so by bridging the two terminals 'b+ and rem' with a piece of wire, positive on the bridging wire, and negative on the ground terminal, or vice versa, i'm not sure which one goes where... can i do the same with a car battery?


Answer
Hi,

A car battery will work to power your amplifier, for as long as it can hold a charge.  You'll need to have some method of recharging it.  Be aware that a typical automotive "starting" battery is not designed to be repeatedly drained and recharged; if the battery is completely discharged more than a couple times, it will be ruined.  A "deep cycle" battery is designed to be discharged without damage.  Also, automotive batteries tend to produce hydrogen gas, making them a fire/explosion hazard.  I wouldn't recommend using one inside a home.

A better option is a 12-volt power supply.  These are widely available in a range of sizes; power supplies that can produce more current tend to be more expensive.  To get an idea of the amount of current capacity you need, check the size of the fuse built into the amplifier, or look in the owner's manual for a current rating.  

An AC to DC adapter like your friend used will let the amp power up, but it doesn't have enough current capacity for normal operation.  As you turn up the volume, the amp requires more current.  A 1000mA converter will quickly be overloaded; either the voltage will drop, causing the amplifier to shut off, or the converter will be damaged.

As for wiring, your friend had it right: the B+ and REM terminals will connect to the positive terminal of the power supply or battery, and the ground terminal at the amp will connect to the negative terminal of the supply.  If you want an external switch to turn the amp on and off, you can put a toggle switch in-line on the wire going to the REM terminal.  

Hope this helps!

Brian