I want to make a 12v to +/-40v power supply for 680 Watts Car Amplifier

BEJOYJG

Joined Dec 8, 2017
8
Hii everyone .

I want to make a 12v to +/-40v power supply which can supply a power of minimum 680watts for powering my car amplifier.So i've went through many websites for getting a circuit diagram for that. But i've got only 220v AC to +/-40v converter circuit diagram. I've uploaded the circuit diagram which I got.

Can anyone please help me to make a +/-40v 680w power supply from 12v dc(car battery output) by either making any modifications to the circuit diagram which i've uploaded above or by providing a new circuit diagram for my requirent.

Can anyone help me please ...

Mods Note:
This thread was split from -- 12v dc to +\-35v dc for amplifier .

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MrChips

Joined Oct 2, 2009
30,939
That circuit will not work for your situation. It takes 220VAC input and delivers 40VDC.

Car amplifiers already have built-in DC-to-DC boost converters.

Joined Feb 20, 2016
4,495
You must have some great 12V battery to run a 680W output for any length of time. Have you looked at the required current?
And that does not even start to mention how dangerous having that sound level in a car would be.
Why in the world do you want that much power?
Although this is most likely "advertising power" not RMS power. Have a look at your amp and see what the real power rating is.

BEJOYJG

Joined Dec 8, 2017
8
You must have some great 12V battery to run a 680W output for any length of time. Have you looked at the required current?
And that does not even start to mention how dangerous having that sound level in a car would be.
Why in the world do you want that much power?
Although this is most likely "advertising power" not RMS power. Have a look at your amp and see what the real power rating is.
I'm having 4 speakers in my car each of 160w and 4ohms inpedence. So now i'm gona make an amplifier for running those speakers. And I wish to create an amplifier with TDA8950th ic. The supply power to TDA8950th is +/-39v. Thus only I wishes to make an amplifier of that much power. I'm having an 80ah 12v battery in my car. What do you say if it can provide me enough power or not.

Regards
BEJOY J G

BEJOYJG

Joined Dec 8, 2017
8
That circuit will not work for your situation. It takes 220VAC input and delivers 40VDC.

Car amplifiers already have built-in DC-to-DC boost converters.
Yeh
I know this circuit needs 220v ac input
My doubt is that if making some small changes, can be used to convert 12v dc to +/-40v dual power supply.

Joined Feb 20, 2016
4,495
You need to check your speaker specs. I doubt they are "real" 160W RMS, probably 50W and 160W Peak Music Power.
And it is a good idea to have your amplifier rated at well below the speaker max power in the interest of not blowing your speakers up.
Also, running anything like that sort of power in a car is quite, well, I don't know what to say nicely, so, let's go with "unwise".
If you insist on that sort of dangerous sound pressures, at least do it while you are alone in the car and don't damage other's ears. I speak as one who has hearing loss and believe me, you will miss it when it is gone. It does not come back.

And no, you cannot make small changes to that power supply circuit to make it work.

Here are some....
https://www.aliexpress.com/item/HP-...oard-500W-with-Protection-DC/32805161621.html

You can use a couple of lower powered ones, and have each channel supplied separately...
https://www.aliexpress.com/item/12V...id=a9903058-d118-462f-8ce3-b84b209f0685&tpp=1

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BEJOYJG

Joined Dec 8, 2017
8
You need to check your speaker specs. I doubt they are "real" 160W RMS, probably 50W and 160W Peak Music Power.
And it is a good idea to have your amplifier rated at well below the speaker max power in the interest of not blowing your speakers up.
Also, running anything like that sort of power in a car is quite, well, I don't know what to say nicely, so, let's go with "unwise".
If you insist on that sort of dangerous sound pressures, at least do it while you are alone in the car and don't damage other's ears. I speak as one who has hearing loss and believe me, you will miss it when it is gone. It does not come back.

And no, you cannot make small changes to that power supply circuit to make it work.

Here are some....
https://www.aliexpress.com/item/HP-...oard-500W-with-Protection-DC/32805161621.html

You can use a couple of lower powered ones, and have each channel supplied separately...
https://www.aliexpress.com/item/12V...id=a9903058-d118-462f-8ce3-b84b209f0685&tpp=1
In each speaker it is written as 160w 4ohm
So only i've chosen this much powerful amplifier and not to blow others' ears

Joined Feb 20, 2016
4,495
Try running on lower power in the car to see how it works. You don't need to have an amplifier rated at the speaker power. In fact I'd say make it at the most, half the speaker power. Going by what I've seen written as the speaker power ratings, even half that is probably pushing it. A lot of speakers are rated in what I think is advertising power, or marketing division power, and nothing like real power ratings.
My 15inch Tanoy Monitor Gold speakers were very heavy, and had a die cast frame. Their rating was 80Watts RMS. They have never been driven over 40Watts and that produces really loud levels. Then I have seen speakers that are labeled as much greater power that the Tanoys but weighed just a fraction. Not real at all!

Just remember, look after your ears

BEJOYJG

Joined Dec 8, 2017
8
Try running on lower power in the car to see how it works. You don't need to have an amplifier rated at the speaker power. In fact I'd say make it at the most, half the speaker power. Going by what I've seen written as the speaker power ratings, even half that is probably pushing it. A lot of speakers are rated in what I think is advertising power, or marketing division power, and nothing like real power ratings.
My 15inch Tanoy Monitor Gold speakers were very heavy, and had a die cast frame. Their rating was 80Watts RMS. They have never been driven over 40Watts and that produces really loud levels. Then I have seen speakers that are labeled as much greater power that the Tanoys but weighed just a fraction. Not real at all!

Just remember, look after your ears

ebeowulf17

Joined Aug 12, 2014
3,307
Try running on lower power in the car to see how it works. You don't need to have an amplifier rated at the speaker power. In fact I'd say make it at the most, half the speaker power. Going by what I've seen written as the speaker power ratings, even half that is probably pushing it. A lot of speakers are rated in what I think is advertising power, or marketing division power, and nothing like real power ratings.
My 15inch Tanoy Monitor Gold speakers were very heavy, and had a die cast frame. Their rating was 80Watts RMS. They have never been driven over 40Watts and that produces really loud levels. Then I have seen speakers that are labeled as much greater power that the Tanoys but weighed just a fraction. Not real at all!

Just remember, look after your ears
Yeah, audio wattage ratings are comical. Back when I got my Harmon Kardon receiver over 20 years ago, I compared it to similarly priced Sony, Pioneer, JVC receivers, all claiming 100+ watts (at ludicrous distortion figures if you dug deep enough to find them.) The HK would go much louder while staying much cleaner despite its meager sounding 35W rating. But those were 35W at fairly low distortion specs. Still love that receiver, and still don't trust over simplified audio specs!!!

yourownfree

Joined Jul 16, 2008
99
With car audio You usually use separate amps for bass and another amp for highs and yet another for mid range. Not one amp does it all.
But in either case if the sound is going to be anything as clear as you want for the mid range for example then the efficiency of the amp will only be about 15-45 %. In other words it takes 100 watts of power to make 15-45 watts. You shouldn't run your speakers at maximum output. If its rated as peak envelope power of 160 watts divide that by 4. or about 40 watts would be the maximum. Plenty enough power. If you blast too much power through your speakers it will sound like #$#$#. If you run your bass speakers through the same amp it will sound nasty. The bass thumps will consume a lot of power and when that happens it leaves very little left for the other sounds. Lets suppose you do want to do 40 watts per speaker which is about 160 watts for all four which is about 400-700 watts total power you would need for the power supply. 700 watts divide by 12 volts is 58 amps of current but that is only at maximum. Doubt if you will ever reach that, meaning all speakers cranking a single tone pushing it to the limit. Music goes up and down so realistically you will be using say maybe 10 amps from your battery or so running an average of only maybe 120 watts. Just a thought.