Ok, lets say for a second I'm totally insane...

If I wanted to hook an aftermarket headunit up to the mains in my house I'd need a transformer to step down to 12v right?

Anyone good at electronics help me with this?

a) Would it be better to get a 14v transformer as a lot of HU's seem to like this voltage more than 12v.

AND

What about ampage? Am I gonna kill the HU if I'm not careful with this?

ampage is drawn not pushed, voltage is pushed so you can't 'over amp' something only up the voltage.

out of interest why would you want to run a car stereo in your home :confused:

Car stereos require a very high current to run properly. 15-20 amps isn't unrealistic , and most 13.8v transformers will only do 5 amps or so. High output ones are very expensive indeed.

An alternative would be to run the stereo off a car battery with a battery charger hooked up to it , though you wouldn't be able to run this all day without flattening the battery.

out of interest why would you want to run a car stereo in your home :confused:

Putting in a new bathroom, and I thought I may be able to save some money by dropping an old HU into the bathroom to run the 4 speakers that are now either end of the bath.

My idea was to grab a transformer, run it through the wall and recess the HU by the bath. Ta-dahh, CD player with remote in the bathroom for peanuts.

It seems peanuts isn't the way it'll be.

I'll have a nosey for a transformer with a high amp rating, and see if this is worthwhile persuing.

Cheers for the help both of you...

Definitely cheapest to get a battery + charger. It's something my dentist in NL had fitted to their office, probably to save the space.

As for current required, depends a LOT on the volume used, and how much bass is in the tunes you play.

Using a charger + battery would work well, I'd get a maintenance free battery though rather than one with the top-up-holes-that-you-can-unscrew, just to be on the safe side.

As for the bathroom use - you'd definitely want to keep battery + transformer out of the room, only feed in the 12V, fused on both the 12V + transformer mains side. I'm guessing you'll keep away the HU from where the water is going to hit it

Speaker-wise you may wanna look into waterproof ones, car ones will work as long as it doesnt get hosed

Definitely cheapest to get a battery + charger. It's something my dentist in NL had fitted to their office' date=' probably to save the space.

As for current required, depends a LOT on the volume used, and how much bass is in the tunes you play.

Using a charger + battery would work well, I'd get a maintenance free battery though rather than one with the top-up-holes-that-you-can-unscrew, just to be on the safe side.

As for the bathroom use - you'd definitely want to keep battery + transformer out of the room, only feed in the 12V, fused on both the 12V + transformer mains side. I'm guessing you'll keep away the HU from where the water is going to hit it

Speaker-wise you may wanna look into waterproof ones, car ones will work as long as it doesnt get hosed [/quote']

I have 4 waterproof 'marine' speakers all set up. They only have 12 or 15W RMS and no sub (although they had a nice waterproof sub )So I'm not thinking loud, just something to make the bath relaxing.

Found a 23amp 13.8v transformer but it's £99. Still tempting as it means it's the only thing in there apart from the HU.

Not sure a Battery and charger will fit, and even if it did the cost of a battery, charger and all the work mounting it in place (plus space taken up) would probablly come near the transformer cost.

The HU will be in a dry place, initial idea was to get a marine HU as well as the speakers, so it's all waterproof. But again, cost seemed prohibitive. Plus only a choice of about 3 HU's

Alternative idea is find a cheap HI-FI system that can fit in the bathroom I guess...

Edit:

Ooh, found this for £70

Input voltage - 110&220 VAC +/-15%, Output voltage - 13.8 VAC Fixed, Output current 22A - 25A Surge

If I get a cheap HU, I reckon this is more viable. Hmm, Isn't this sort of thing fun...

For a bathroom I'd just run cables to the speakers into a nearby bedroom and power them off a home stereo , probably with a speaker switch to select between the two sets

For a bathroom I'd just run cables to the speakers into a nearby bedroom and power them off a home stereo , probably with a speaker switch to select between the two sets

Nah, too easy. The study's next door could plug it straight into the MP3 disco machine that is my computer.

I'm gonna do it just for the challenge now

I'm thinking 10amps or so should power a cheap HU (all I need is 2 channels of around 10-20w RMS) If not, it's 20 quid more for 20amps.

Found a cheapish JVC HU that should be ok with 10amps

It'll be a laugh if nothing else.

P=IV

so I=P/V

so 20W/12V=1.2A

oviously that is per speaker and there will be a certain amount of losses involved so you should be ok with what you have

thinking about the above my subs alone are drawing 100A alone :eek:

how about a split mode pc supply provided you can keep it loaded up. not sure how you would manage the presets backup though. I plan to do something like this at home in the kitchen. Just cos your HU has 2x20w RMS doesn't mean that your HU will continuously draw anything like this.

why not just fit a flat wall mounted stereo in the bathroom opposite the bath and feed it from a high level spur?

why not just fit a flat wall mounted stereo in the bathroom opposite the bath and feed it from a high level spur?

Can't find anything decent that doesn't have built in speakers or doesn't look like it's made of paper.

It started as an idea that seems to have worked into a mission.