I am getting close to upgrading my stock stereo. My plan is to keep the HU, and upgrade the speakers. If I find afterward that I need an amp, then I am preparing for that as well. I am currently looking at Polk db6501 for the fronts and db651S for the rears. The reason for these is twofold. First I’m assured that they will fit with no modification to the door and side panels and second some NAMers claim that they are louder with the stock amp that their former stock speakers. Personally, I find this hard to believe, but if they’re right, then I’m done.

If not, then I need to add an amp which is where things get a little more complicated. Based on a recent post I understand that there’s 16.5 x 10.5 x (1.5 – 2.5)” cavities under the seats (thanks PGT). The difficulty I’m trying to work through is in the amp wiring which may directly impact which choice I make. Anyone know of a how to on wiring an amp into the stock HU? I can see this being a bit beyond my talents, but maybe with a step by step I could muddle through it. If not, then I see three choices. First, maybe I can find a local expert to help me through this part (doubtful). Second, pay a shop to handle this part of it. Third, according to Crutchfield the Blaupunkt THA475Pnp amp has an optional wiring harness and extension which requires no wiring. Just plug it into the back of the HU and plug the existing harness into it. At $450, it’s a pricey option, but probably cheaper than paying a shop.

During my searching through old posts I did read about a number of problems people had with noise. Was the cause of this ever figured out? The few I read which mounted amps under the seats this didn’t appear to be a problem. Anyone have any experience wiring an amp into the stock HU which they can share? Any comments on where I’m headed or is there anything else to account for or consider?

 

What do you mean by HU?
I am considering redoing my Stereo System as well. I leaning towards and entirely new system with an AMP. But I am still on the Fence.
As far as mounting the AMP. Most of them need some room to breathe if you are going to be putting a lot of power into them.
I didn't really consider all my options about where to mount the AMP, but I am leaning towards the trunk, maybe bolted onto my back seat.
You might want to check the specs on those Polks. You should be fine in most cases, but if you want it real loud and get a big amp, you might blow em.

 

If it helps any, these are the connections to the stock HarmonKardon amp.

http://www.gbmini.net/HKconnections.pdf

I used this to intercept the high level input signals for a subwoofer amp and it worked great. I haven't messed with or researched for a Head Unit (HU) swap, so I'm no help there.

 

Head Unit being just the receiver?

 

Escuse my Ignorance on this matter (I'm still new), but is the HARMON KARDON system worth upgrading or should I just get rid of it completely?
It says HARMON KARDON around my speakers, but nothing on the receiver. It has a decent sound but it's not loud and sounds crappy when it's turned up.
In my experience, stock radios and amps are crap, but every once in a while, you'll find one that only needs one part replaced ie; good speakers, crappy receiver and visa versa.

 

HU = Head Unit = Stereo = that thing in your dash that plays music.

 

I figured as much. Thanks for the Clarification, Flingger.