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Convert nice Car Stero to a better Shop Stereo Answered

I've seen it done before way back when.  Want too save a few $$ and hook up a brand new JVC Car Stereo to be the main stereo in the Garage Shop.  What is the best way to convert 12 volt to 120 power supply?  Just use a power converter?  anyone done this here lately?  I tried searching on instructables but just found how to hook up to battery...


You could do it with a PC power supply. Cheap and simple.


Hmm. Depending on the wattage of the stereo and the wattage of the PC supply, when the bass kicks it might cut out due to the excessive amount of current. Maybe it would be best to couple a PC power supply with a one farad capacitor.

Looking at a 500W spec PSU, one 12V rail is 16A - 190W - probably enough. Putting big caps on switchers makes me nervous.


The cheap surround sound system I have at home (~$219) has a bass rated at 350 watts. Note, that it also at 120VAC. I would bet that this has a bass at least rated at 200.

The cheapest sub woofers I could find were 60 euros. They're 400 watts, twice the power of a single 12 volt rail.

I wonder if that's real RMS power, or one of the weirder interpretations of "PMPO"

Adding a cap isn't going to give you any more power.


No, it is the peak. The root mean square is 120 watts.

Adding a capacitor will not give you more power, by law of conservation of energy. It acts as a "energy boost", akin to a rechargeable battery. When the bass hits, the power supply cannot provide enough current. The capacitor provides the overlap that the PS cannot, thus keeping it running.

I wouldn't think that a computer PSU would be any good for this anyway. They are sensitive, very sensitive, and this is on purpose. It will cut out if there is a sudden power spike in usage. Why? When you have a computer, there is one reason why a sudden (large) power spike would occur: a short.
Please note that by large, I mean large in the range of 20 ~ 30 Joules (20 ~ 30 watt-seconds).

Pay $20 for a 12 v. supply wall wart.  Probably needs to be an amp or so.  Or you could just build your own.  You'd need a 14 -20 volt transformer,  a 12 v. regulator a capacitor some wire and a box to put it in.  Google "12 volt power supply schematic" for the diagram on how to hook it up.

If its a reasonable radio, it'll need more oomph than an amp I suspect.


Got both... I'll go see if I have either of the 2 in my box of old electronics.  Thank you for the paths to try!  Thank you both!