power from lighter socket for a home theater sub, safe?

[TI-CAVA]

thinking of upgrading my audio setup using a home theater...

i want to run a 12v line from the lighter socket all the way to the trunk to power a sub, my questions are:

is it safe?

can this f@ck s%&t up?

where to get 12v when the key is in only?

thanks!

[hungt1999]

If you use the cigarette power outlet, it is already limited/protected by a 15A fuse

you could also tap into the power for the radio at the wire harness behind the radio (yellow wire on the radio wire harness, it is controlled by the ignition key turn to ACC or ON). The radio is on a 10A or 15A fuse also.

Other than that, I don't know of any other location that is controlled by the ignition key (wipers maybe?)

don't forget to use a proper gauge wire

[TI-CAVA]

what gauge should i choose?

also, can i pack the audio lines and the power in the same route or there will be too much crosstalk and interference?

should i just put the sub in the trunk or open an air vent for the sound to get into the cabin???

[hungt1999]

how much power do you need?

at 15A, your maximum theoretical power would be 12V x 15A = 180Watts

Any wire larger that 14 Gauge is good for 15A current

I don't think there is a need to run the power wire far from the audio wires, the power wire is DC current. It should not interfere with the audio wires. As a matter of fact, the factory radio harness have all the power and audio wires altogether and all these wires are unshielded.

But I don't understand, you want to use a 'home theater' equipment, that runs normally on 120VAC? are you going to bypass the internal transformer inside the hometheater amp?

[TI-CAVA]

yeap i'm gonna bypass the transformer, i dunno how much power does it draw, 70w is market in the sticker of the HT, but @ full power, i'm not gonna run it not even close, just need a bit more bass.

6x9's are on they'r way, i'm planning on putting them in stealth... but i need to find the same type of carpet to make it look stock...

[Bitter]

so you're going to try to run a 120v home theatre subwoofer from a power inverter in the car?

[TI-CAVA]

nope no power inverter, just bypass the transformer and plug the 12v directly as if the transformer were giving them naturally

[MrGiggles]

Are you 100% sure it runs on 12v DC with the transformer bypassed? I wouldn't run a HT sub in a vehicle anyway, the enclosure is tuned differently.

I've read that if you run the power wire and RCA's together you will get interference, never tried it though. I would run them opposite just to be safe. I also wouldn't run the amp solely off the cigarette lighter. Get a bosch relay and use that instead.

[lancelantier20]

you should have no problem running all the wires together in the same path i have complete alpine system setup and i have no interference i would use a 14 gauge and up for the power that is what i use on mine im running to 12inch w7 jl audios in a custom box and i have beautiful bass that is my suggestion you can also run the power cord directly from the fuse box the ignition fuse you can run it from there but thats only if you wanna run the power wire solo from the others

[Bitter]

Originally Posted by TI-CAVA

nope no power inverter, just bypass the transformer and plug the 12v directly as if the transformer were giving them naturally

oh, one of THOSE speakers.

[TI-CAVA]

those? what kind are u talking?

[Bitter]

the shitty little self powered "subwoofers" that come with shitty little home entertainment systems. THOSE kind.

[TI-CAVA]

well, it is one of those, but not so little and not so bad, i mean, for being a Durabrand cheapo, sounds good, obviously if u compare it to the sony muteki in my room......

but anyway is a temporary solution... until i can pull my stealth mounted 6x9 all around

[Bitter]

its not that hard to get them in the rear deck cleanly, you just need to make the adaptors like i did. mine showed in the rear deck but its no big deal.





would be very easy to make a false shelf to put the fabric level with the speakers using a sheet of hard foam board covered with fabric.

[hungt1999]

before you run wires, just test out your HT first with 12VDC from the car to see if it works first