I currently have a jvc HU  and it only has one rca. i have both rca cables wired to my  2 channel amp to my current subs, I want to install a second amp for my front door speakers. 

I just ordered new subs and a amp from IA. So it will be two death row's running on a 20.1 and a power acoustik 2 channel amp for my doors. So how would I do this or do I need a new head unit? 

What model hu? You might be able to split the signal, but a new hu would probably yield better results.

JVC kdr330 50x4 Car CD Player with Dual Aux Inputs

 

this model. so is there anyway to hook up a mono amp along with a 2 or 4 channel amp for my doors? if not could you recommend a good hu for under a 100 that would be able to. I kinda blew my budget getting the new subs and amp. I just don't want the subs to overpower my door speakers.

You could run a pair of RCA splitters(1 female to 2 male). I see that unit is has 2.5v preouts, so when you run splitters- you will be getting 1.25v to each plug. This shouldn't be an problem.

Sample of splitter- not that I recommend the brand

http://www.amazon.com/Pyramid-RY6-Male-Female-Adaptor/dp/B0007LCKJQ/ref=sr_1_3?ie=UTF8&qid=1378798605&sr=8-3&keywords=1+male+to+2+female+splitter

If you run a splitter, you will have to use the amp gains to adjust your front/rear bias(fade), as obviously the radios fader wont work.

I also suggest upgrading the deck though, the splitters will work. but you can buy a deck with multiple preouts for 100 or less. that is a fraction of what the IA amp and subs cost. Just Saying. EDIT- just saw you asked for suggestion, My Pioneer came from Walmart for less than 125, and it has f/r/sub preouts, and internal crossovers and sub control.

Edited September 10, 201312 yr by Leedogg

As a heads up, there are a ton of headunits that only give you 1 pre-out since on average you should be running bass mono anyways. Also, when you split a subwoofer out that the voltage does not split the output voltage in half like previously stated. It should remain the same over both sides without issue.

Rough analogy, but it's like running multiple runs of power wire from front to back of car. I'd sure hope I didn't drop half voltage per run of wire. If it's 12 up front it'd be 12 in the back on all runs. Same should hold true for the rca. I personally use a knukonceptz karma SS splitter currently for my kenwood9990HD (1 sub out) and it works great.

With all that being said. I would still recommend an upgraded headunit since you should definitely have separate front, rear, and sub outs.

Edited September 10, 201312 yr by nadcicle

 or you could get a pre amp

Kenwood KDC-HD455U

Thanks for all the help guys. just 3 more questions. Is this HU descent, and if I was to use the split for now I would basically hook the rear rca to the amp running my door speakers and the sub rca to my mono amp. Then adjust the 2-4 channel amp for my doors. Lastly I've never ran this much bass before, I've been running some walmart duals off a pyle amp so should I still be able to hear my music without a door amp? my current door speakers are fusion. (sry for so many questions)

Edited September 10, 201312 yr by Cptsnuggle

As a heads up, there are a ton of headunits that only give you 1 pre-out since on average you should be running bass mono anyways. Also, when you split a subwoofer out that the voltage does not split the output voltage in half like previously stated.

 

Thanks for the correction- I was always told that, I apologize for the inaccurate info.

 

 

I think the Kenwood KDC-HD455U is a much better deck than what you are currently running, for the system you are about to have.

I agree with Leedog. Get a better hu that has at least 2 rca's out. one for front stage and one for the subs.

Replacing the head unit or maybe purchasing a pre-amp processor/eq would be ideal... which ever fits your budget and needs a bit more.

thanks for the help guys. I post a build log soon on the IA sub-forum.