Quick question about hooking up a HU and Amp

[D-DAY 10+ year member]

I have a DEM-P7800MP and I am going to run a 2 chan amp to the front speakers. The HU has RCA outs for Front, Rear, and Sub. When I hook the RCA cables for the front speakers up to the amp, does the HU still push power thru the speaker wire running from the back of the HU to the speakers. (Just like a regular HU install w/o the amp???)

Click to read more...

 

[disturbedfuel15 10+ year member]

It really depends on the head unit itself. The only way to find out is to try it out. Hook up the front RCAs, and unplug the front wires coming from the head unit. If it powers the front speakers, great. I know mine is really shitty in the fact that you must either have ALL rcas or ALL wire. It won't do both at the same time, which pisses me off a bit. Good luck!

 

[dkguitarist 5,000+ posts]

why would you wanna use headunit power anyways?

and you'd be mixing clean power with dirty hu power too.

but the only way is to try it out like said above.

 

[D-DAY 10+ year member]

Well I was thinking that maybe I could use the unused HU wiring for the front speakers to power some tweeters. I just really wanted to know if the HU kills the power to the front speaker wires when you hook up the front RCA cables. It probably won't work, I was just trying to think outside the box.

 

[disturbedfuel15 10+ year member]

My guess would be, it kills the power to the wires if you use RCA.

 

[KaeZoo 10+ year member]

In every head unit I've ever seen, plugging in an RCA cable to any output has no effect on the speaker outputs.

 

[Colt9699 10+ year member]

i use rcas for my sub amp and for my front speaker amp and still use HU power for my rear fill soas far as i know using the rcas does not kill the hu's ability to run speakers.

so for instance i am running fronts on a seperate amp and i could add say a set of tweets run by my hu's front speaker power.

 

[D-DAY 10+ year member]

i use rcas for my sub amp and for my front speaker amp and still use HU power for my rear fill soas far as i know using the rcas does not kill the hu's ability to run speakers.
so for instance i am running fronts on a seperate amp and i could add say a set of tweets run by my hu's front speaker power.

That's what I needed to know. Thanks.

 

[EzekialPhoenix 10+ year member]

most (if not all) of decent head units these days have a function that allows you to turn off the internal amp if you so choose.