Car head-unit on my desk

Howdy!

So recently I took up a project for myself which (in short) involves hooking up an aftermarket car head unit (12VDC) to my desk (120VAC) and then hooking up car speakers of my choice, down the road building my own box for the speakers. I would then have a full-featured car head-unit on my desk with which I could run my computer through, as well as radio and CD and possibly eventually bluetooth audio and HD radio.

Simple to many of you, but I know only the basics when it comes to DIY: electronics edition.

So I am here searching for advice (possibly a less ego-crushing way of asking for help?).


The first thing I am looking into is converting 120VAC to 12VDC. I've done a little bit of searching and came up with this rectifier as my starting point (LOL at the brand--but I did buy a plastic storage device a long time ago from them and it hasn't gone up in a cloud of smoke yet).
I know that it converts 120A>12D, as I need, but I am unsure if I am to worry about amperage or power. Yes? No? I assumed it would draw only as much as the connected device needed. But I figure I should double check anyways.
I would be splicing the output wire and connecting them to the power input to the head-unit.

And that is where I would like to start. My main concern at this moment (everything else should be fairly simple if I can get this running).
If you would not suggest the product that I linked to, please point me in the right direction; I would like to get this right the first time

This is the head-unit that I eventually plan on purchasing if I can get it running. I have a slightly older head-unit as well as a pair of not-new 4x6 Pioneer car speakers at my disposal first, so I guess we'll see how it goes with those.

Whether or not I can get it to sound good remains to be seen. Even if it doesn't, it's a fun little project for me and I think I could use the experience.

Thanks in advance!

 

Neat, but sound fidelity on car audio equipment is never as good as home equipment. Well, maybe not never, but you are never going to reach the goodness you can with home equipment.

I wouldn't worry about the power coming out of that walmart voltage converter. The quality of the power getting to that head unit in an actual vehicle is going to be much worse. It might not be able to supply the amount of juice you are going to need though. Instead of buying several you could get a 12v power supply by lightly modding one from a computer.

 

12 volts is just the battery voltage in a car

The electrical system actually runs at 14.4 volts.

 

Everything is made to run at 12 volts just as well as 14.4 so that really doesn't matter.

 

I'm with trottel - get yourself a PC power-supply. - You'll be running the speakers directly from the head unit, I assume, and therefore will only need 200W (most average HUs I've seen are rated at 50W/channel, 4-channel) max supply, which a pc supply will do easily.

No wattage rating mentioned on the walmart one you linked to.

Oh, for the record, you get extra points if you mount the rear speakers in your seat lol.

 

it does matter. The closer you are to nominal voltage the easier it will be on the internal dc/dc components.

The difference between 12 and 14.4 volts is 17%. That's a pretty big delta for components to make up.

 

if you do a search on instructables.com, they have an ible on turning an old power supply into a source for car audio equipment.... havnt tried it myself but it appears to work great

 

The head unit and any amps are made to work perfectly fine at either voltage. I've never heard of any going bad because they were used without the engine running.

 

No, it doesn't.

Yes 17% is a large difference, and on other equipment that (for whatever hypothetical reason) ran 14.4V, it might be an issue, but the fact of the matter is that the equipment is designed specifically to be able to operate withing those voltage ranges, because being able to run on 12V is a common requirement of car audio equipment.

 

Thank you for all of the replies.

Yes, the fact that I can run my car stereo on battery as well as with the alternator chugging along is a sure sign that it'll accept either of those voltages -- therefore I'm not too worried about that; I should have specified 12 to 14.

Trottel: Yah, I'm not putting much hope into the fidelity; I have a decent home-theater to work with that task.
If I'm really that disappointed in the up-close performance, I'd probably take it out to my garage to listen to while I work on my other toys. Big garage = poor acoustics = perfect for car stereo. Then I suppose I'd settle for something else on my desk. But I guess we'll see when the time comes

crazycanuk: Thank you for the suggestion. I have looked into it myself but I concluded that I would rather leave the electric alterations to someone who knows exactly what they are doing. I'm just a guy

Now, can anyone point me in the direction to a compatible PC PSU?

 

Hell, anything that can supply the amount of power you're looking for (250W would be a safe bet if you're not running an amp).

Just buy a scrap pc and rip the psu out of that. If it doesn't have a discrete power button, on most supplies, you'll have to switch/short the green wire to ground (black).

 

Do desktops typically operate on DC? I've been looking at notebook AC adapters but most are 16V+ and less than 100W.

I found this and figured it would work as long as I only hook up 2 speakers.
Kinda pushing it but they're strangely hard to find..

 

Yes. All power coming out of a Desktop PSU is at +5/+12/0/-5VDC (IIRC)

5V is generally red, 12V yellow, 0V (Ground) Black.