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I want to change my speakers which have an ac input into a dc input so I can have them portable Any help ???? Answered

Basically I really need help here. I just bought a set of old small speakers and I wanted to turn the Ac input into a Dc input and I have no idea how to any ideas ?? The step down transformer is inside one of the speakers and I'm not sure how to make it into Dc
Money's not really an option but I don't really want to buy more speakers

most appreciated Ed :D


ok haha thanks it sounds like I have my work cut out whee then. But I guess the end resultwill definitely be worth it :)


3 years ago

I assume that by "turning ac input to dc input" you mean to power the speakers, not a signal input, and that the speakers are like computer speakers, and have a small amplifier built in.

The easiest, least invasive solution would be to use an DC to AC inverter. Nowadays they are pretty cheap, and can come in quite handy if the power goes out. They can also power other things too, like small lamps, computers, etc, and even the cheapest ones can deliver 100W or there abouts! You can even make one with a few MOSFETs, a MOT, and a 555 timer or arduino!

Inside most electronics (or sometimes a separate power brick) is a power supply that converts 120V AC into a low voltage DC. You will need to locate the output and figure out the voltage and current rating, and then replace the PSU with a DC source you want like a battery. If the voltage does not match your DC source, then either change out the DC source or use a boost/buck converter or other type of voltage regulator.

Say you figure out the voltage is 5V and the current is 1.5 amps, and you just so happen to have a 12V battery that can safely deliver 700mA of current. You can't just use a linear voltage regulator because the output current would be the same as the input current, and the speakers need more than 700mA. Instead, you would have to use a buck convertr, like one of those USB car phone chargers. Inside them is a buck converter which will lower the voltage and increase the current proportionally.

Ok thank you soo much this is really going to help :D looks like I got a project to do tonight! I will proably look on google how to make a inverter. And Once again thanks for the help

Making an high power inverter can be quite the challenge, and you will need to buy MANY MOSFETS. Decent one's like IRFP260's are not the cheapest either. Good luck. Trust me when I way you will need 20 of them because they are so easy to kill.

Here is a video of an inverter that is surely overkill for your application,

Well Basically inside my speaker is the step down transformer with the 240v going in and once the power has been stepped down there is three wires that go straight into the curcuit board. One black which is labeled gnd and two blue labelled ac1 and ac2 what do I do with them