So /diy/ I'm trying to figure out a way to make a speaker

You aren't just a tech moron...
How about giving us some relevant info such as make/model.

it'll say how many volts on the power adapter

>>1014103

Wattage = Amperage x Voltage.

Amperage = Wattage divided by
Voltage

Voltage = Wattage divided by Amperage


As long as you know the value of two of these, you can calculate the third.

Therefore, to run a mains speaker on a car battery. In the USA mains voltage is 110-120v AC. So at 12v you'll need ten times the amps to convert it from 120v to 12v. If in the UK Mains voltage is 240v, therefore the amperage will be twenty times as high, in order to run at 12v.

If your speaker is 60w @ 120v that's 0.5A, at 12v it would require 5A. If it's 60w @ 240v then it's 0.25A, therefore at 12v it will pull 3A.

This does not account for efficiency losses, nor does it guarantee that a car battery can run the speaker for any significant length of time.

You would need to know the rated Amp hours of the battery, then use your voltage conversion to calculate how long you would have sound for.

At 12v a 1A/h battery will provide, unsurprisingly, one hours runtime. So a 24A/h battery could deliver a days worth of sound at 1A, or two days at 0.5A half a day at 2A etc.

Usually car batteries are capable of heavy surges, over 80A cranking power etc, but obviously they won't last for days or many hours at excessively high wattages.

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>>1014107
I have this from the manual

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>>1014131
And this

>>1014131
>>1014132

If it helps its a sony gtk xb7

>>1014131
Yeah it tells you: 120v, 60 watt so .5 amps.

I'd think a transformer and car battery would be able to run your speaker for at least a couple hours. I know in my car, I can play the radio for 2-3 hours with the engine off before I kill the battery. Need more time, add more batteries in series.

>>1014146
>I think a transformer
I mean inverter

>>1014146
I think you meant in parallel

>>1014103
>>1014133
Ok, from what I could understand, you want to make a 12V DC int to 110V AC to plug your speaker. If you want to do that you could just take a UPS and charge the battery, but would be the most inefficient and dumb way to do it. Other option would use a dedicated inverter as >>1014148 said, but wold still be inefficient. Most speakers have a AC > DC converter inside, instead of using a DC 12v battery, then transforming in AC 110v to plug the speaker to it them transform in DC again to use it, you could just open it and plug the battery direct to the DC input of the of the amplifier. You just need to see if you have the right tension. It could be a 12V DC on the inside, but it could also be other tensions such as 16V or 20V, you need to check it. It also seems that it use a digital circuit for the BT and the USB input, so it could also need a 5V (with you can get with a 7805 if it is not too demanding).

Check this video (he does that to a TV digital converter, but the process would be the same):
https://www.youtube.com/watch?v=lVKm45r0uUY

usb battery with a usb to dc barrel plug or whatever you need. My battery is 26000mAh and can do up to 4amps. Cost me 50 dollars and has 3 usb ports. This is a tech q not really diy q

>>1014148
Just buy a portable speaker, or even make one from scratch. Both would be cheaper than buying an inverter and won't involve lugging around a car battery.

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>>1014156
You probably should have run the numbers or googled before posting.

The thing OP posted looks like a mobile-phone speaker, but it's actually a portable monitor nearly a meter tall. (here's a (you) for >>1014160 as well).

If it's eating 60 watts, it'll exhaust your 130wh battery in 130 minutes, whilst drawing 300% of its 20w rating.

>>1014175
That assumes a very efficient inverter