Running a Car Audio System off 240v AC.

[CarlosBarros]

Hi there

A friend and I recently built a 'wheelie bin sound system' by putting a car amplifier (400 watt), speakers (2 X 30 watt RMS) and subwoofer (200 watt RMS) in a wheelie bin along with a car battery to power them. The thing worked very well, running continually for 6 hours. Here's a vid:
https://www.youtube.com/watch?v=Qc7ARy19s1M

Now we'd like to modify the wheelie bin so that it can be plugged into a 240v mains supply or a generator when required. The intention here isn't to charge the battery, only to make mains power an option if the bin is being used at house parties etc.

My friend and I know almost nothing about electronics, so we are feeling our way in the dark a bit with this project.

Could anyone offer any advice? Essentially the enquiry is: can a car audio system be made to run off a 240v mains source?

We were thinking of using something like this:
https://www.southwatercycles.com/products.php?plid=m48b279s606p25655&rs=gb

Any thoughts?

Cheers

Carl

 

[Nigel Goodwin]

That's the sort of thing, but you don't need a twin one.

 

[tcmtech]

A regular 20 - 30 amp battery charger would do just fine as a power source. Just add a extra 100,000 uf or larger audio super capacitor or two to it if it generates too much back ground hum in the audio signal when it plugged in.
Or get one of the newer inverter based ones with the high frequency switching power system in it so it wont hum.

either one will easily power the system when the load is higher but also be able to keep the battery topped off while it is turned down.

Santa's dancing to a garbage can! Cant say I have ever seen that one before.

 

[audioguru]

A speaker's enclosure is supposed to be rigid and not flex. The garbage can flexes too much.

 

[Nigel Goodwin]

A speaker's enclosure is supposed to be rigid and not flex. The garbage can flexes too much.

Well you'd expect it to sound 'rubbish'

 

[Mitch268]

Hey have you made one yet. I really wont to make one of these so i can have it on battery power and 240v, can u just use a battery charger?. and can you please give me a list of what i have to get??

 

[dr pepper]

Well you'd expect it to sound 'rubbish'

It depends on whether you want to run the system totally off the mains without a battery, if so you need a high current psu, very expensive.
If your only going to run for a few hours then a 20a charger in conjunction with a car battery ought to be fine.

 

[CarlosBarros]

Hey have you made one yet. I really wont to make one of these so i can have it on battery power and 240v, can u just use a battery charger?. and can you please give me a list of what i have to get??

Hi Mitch

No, in the end I followed these instructions and modified a computer PSU. I mounted the PSU in the bin and now simply pull out the 12v DC cables from the battery and plug them into to the PSU when I want to run the bin off a wall socket. It means the battery doesn't charge while the bin is being run off the PSU, however.

I have to say it was a waste of time. There's now a 'leisure battery' installed in the bin and it can run the car audio equipment on full blast for about 12 hours, which is far longer than I've ever needed to use it in one stretch. Recharge overnight and it's good to go again. So I've found the PSU unnecessary.

Cheers

Carl

 

[tcmtech]

Hey have you made one yet. I really wont to make one of these so i can have it on battery power and 240v, can u just use a battery charger?. and can you please give me a list of what i have to get??

I built a number of these back in college years ago. All I did was get a good sized battery charger from a garage sale or similar dirt cheap source with a continuous charge rating of equal to higher capacity than the amplifier it was going to run and added a big set of capacitors inside the chargers case and replaced the two leads with large binding posts on the front.

I think I went with a capacitor set of at least 5000 uf per amp of draw which worked out to a power supply capable of running a 500 watt amp on 12 volts being something like 200,000 uf or larger.

I can't recall anyone ever burning one up or having issues and my brother still has and uses one of them I built from around 20 years ago in his shop!