Amp Upgrade/Line Driver advice

[Vypre]

So I was hoping that some of the local experts here might be able to help me out as they have in the past. I'm attaching a rough layout of my system also, might make it easier to understand. So here's the run down, i have an '05 Pilot with my Factory HU, but have replaced all of the speakers to include the sub (still in the stock location). My 4 channel amp just recently blew (Kenwood KAC-648s) and i have to replace it, and how i noticed my quandry... I had the system installed by an installer but have done a lil tinkering here & there. So the HU is running to a Scosche SLC4 LOC (4 ch) via speaker level inputs, and from there the signal goes to a Phoenix Gold TLD66 (6 ch) line driver via RCA. so the first four channels of the Line Driver fed to my orig 4 ch amp, but there is also a Y adapter that splits one pair of outputs from the LOC so that all 6 input channels of the line driver can be used. (yes i know if i was anything more than a novice this would be easier to explain). so 4 channels leave the line driver and goto the 4 channel amp, and the last 2 channels (split via Y Adapter) goto my sub amp. So i've dropped some coin down and ordered my new 4 channel amp (Pioneer GM-D9500F), which has a set of RCA outputs to feed a 2nd amp (as did my old one). (drum roll) So the question here is, which setup should i use?
A: run everything as it was previously
B: Forego the Y adapter and just use 4 channels and the RCA outputs to the Sub amp from the 4 channel

Hope i made that as clear as mud (think the attachment is clear though). below is a full layout of the system in case that info is needed.

HU: Factory
Front: Pioneer TS-D720C Component 6 3/4" - 4 ohm
Rear: Pioneer TS-A642P Coaxial 6.5" (4 way) - 4 ohm
Sub: Rockford Fosgate Punch P3SD210 10" DVC - 2 ohm
Sub Amp: Viper D600.1 750W (mono)
4 ch Amp: Pioneer GM-D9500F (class D, 4 ch) 2~8 ohm 800watts
Accessories: Scosche SLC4 Line Out Converter (4 ch)
Phoenix Gold TLD66 Line Driver (6 ch)

[ED27]

I would get rid of the LOC and line driver and go with a unit that has both functions integrated. Something like the re-Q, JL Audio CleanSweep or AudioControl LC7 will give you a much better frequency response curve at the preamp stage. Otherwise if you want to use what you have as much as possible, add a 2-channel LOC and connect sub output of the factory radio to the line driver. This way you'll eliminate the need of the y-adapter.

What's the reason for keeping the factory head unit? Do you have an EX-L NAV?

[ED27]

BTW, I haven't used a factory head unit in a while. Can you adjust the sub output separately from the rest of the speakers?

[Vypre]

Originally Posted by ED27

I would get rid of the LOC and line driver and go with a unit that has both functions integrated. Something like the re-Q, JL Audio CleanSweep or AudioControl LC7 will give you a much better frequency response curve at the preamp stage. Otherwise if you want to use what you have as much as possible, add a 2-channel LOC and connect sub output of the factory radio to the line driver. This way you'll eliminate the need of the y-adapter.

What's the reason for keeping the factory head unit? Do you have an EX-L NAV?

Well the original reason that i went that route, was the cost. I am on a fairly tight budget and the only reason i'm currently doing the amp upgrade was the original blew. And i haven't changed the factory head unit because i have the RES and don't want to lose the functionality of it as well, it's Dual Zone. I know there are NAV systems out there that also have the Dual Zone but they aren't currently in the budget. So how would i add an additional 2 ch LOC if the HU is only 4 channels? would i splice into the rear channel? And what would be the difference between doing that and just using the Y adapter? The line driver i use has individual gain controls for each channel, so that's how i currently adjust the sub output.

[ED27]

The head unit has a separate output to the sub. It's on a separate harness vs the other speaker wires. Look for wht/grn (+) and blk/wht(-) wires. Where do you have your line driver installed?

[ED27]

nsaspook has some really good info in his install thread. See here:

DDX812 install

[Vypre]

I don't believe i have separate Sub outputs in my pilot. I attached a copy of the actual wiring diagram and only see the 4 channels + tweeters. The line driver is currently installed underneath the center console (passenger side, kinda below the cup holders). And I had monster cable spearker wire run to the sub, so its linked directly to my sub amp under the passenger seat.

[ED27]

Look on the next page of the ETM (150-3). You'll see the sub output labeled B1 and B8. Aside from the RES and NAV functions, all of the radios in the EX range are virtually the same.

[Vypre]

any chance you have that document? I only have that one page that i found awhile ago when i was doing a lil tinkering.

[ED27]

Look at the attached PDF.....it might be for an '06 but it should be the same wires. I have the ETM at home for my '04 so I can double check later as well.

[Groundpound4200]

In my EX-L's deck there was a separate plug for the subwoofer. I would tap into that with another LOC or something like this Alpine Electronics of America, Inc. I used the slightly older unit the PXE-H650 and I picked it up for about $200. 7 channel RCA outputs auto eq and auto time alignment

[ED27]

In the ETM for the '04, the wire colors are the same. You can find it in the 14-pin LT BLU connector which is next to the main 20-pin connector.