The RF amp is woefully underpowered for its intended purpose. It won't 'break' anything if you leave it in place and connect your new HU into the factory harness, but you will have defeated the real purpose of a different HU. The actual output power per channel of the factory amp is less than that of most aftermarket HUs, so you will in effect be downgrading your new HU by leaving the amp in place.
It is a relative simple matter to bypass the amp at its connector (the blue one). I have posted elsewhere in this forum a wiring diagram and instructions for the bypass (do a search on my screen name) on the RF in an '04. As far as I know Nissan has not changed the wiring in the 05 so the proceedure should be the same.

 

Try here for some ideas
http://pac-audio.com/oem1kits/oem1search.htm

 

I used the PAC OEM2 to connect my Kenwood head unit to the factory amp. It's just something in the meantime until I put together all the other things I need to build my "system." Several of my friends have commented that it actually sounds better than the stock RF headunit. If you want to connect your HU speaker output to the speakers, it won't work because the factory speakers are at 2 ohms. You'll either have to replace the speakers and bypass the factory amp or use the OEM2 to use the stock amp and speakers.

 

Thanks for all the great responses. So now I have another question, isnt the intent of the PAC-OEM2 to reduce the output level of the aftermarket headunit to the factory amp?

If this is the case then I thought the headunit needed to send all the power it could to the factory amp and reducing the output level would have a negative effect?

 

From what I understand, the factory amp is expecting low level input just like a regular amp but on a speaker wire rather than an RCA cable. It just needs the signal without the amplification...which is what the OEM2 will do for you. Sending the full, powered speaker output could have adverse affects on the HU or the factory amp. I've had my DDX7015 hooked up this way for about 3 months now and it's been fine.

 

If it was me I'd just toss the whole system. that amp and sub is not worth more than $100 anyways.

 

Sending full power from an aftermarket HU to the factory RF amp will seriously overload the amp resulting in a number of possible bad results - the least of which is serious distortion in its output. It would be possible to totally blow out the amp if one operated the HU at near full output level, afterall the output of most aftermarket HUs is greater than what the factory amp can deliver under ideal conditions.

As I stated earlier, bypass the amp, it is relatively easy to do and avoids a number of potential problems.

 

most aftermarket HU's only output about 11 watts-15 watts RMS. Your saying the amp only puts out as much power as the stock HU about 6 watts RMS? Why would they use an amp then?

just curious, i didn't fall for the rockford system package.

 

The midline and Rockford HUs are essentially the same except the Rockford unit does not have the audio output stages that the midline has. The Rockford HU has barely enough power out to drive an LOC and an aftermarket amp. As a matter of fact some of those who have kept the Rockfort HU have used preamps ahead of the LOC (or a combo preamp/LOC) to get workable gain to their amps.
The midline output is likely in the neighborhood of 6 to 8 watts RMS per channel. The Rockford HU (without the amp) is probably less than 1 watt. Therefore, applying somewhere in the realm of 10 to 20 watts RMS to the input of the Rockford amp is not a good thing to do. Doing so could cause the components of the amp to "lose their smoke".
The amp in the Rockford system is used to provide its 6 or so amps max to each of the connected speakers. The output of the HU is 4-channel (left/right - front/rear). In the Rockford system there are two front door speakers, two dash tweeters, center channel speaker, rear door speakers plus the subwoofer. The amp splits the four channels to all those speaker locations, thus it serves as both an amp and a distribution system.

Have you figured out how they arrive at 350 watts for the Rockford system? There are 10 speakers in the CC configuration, apparently they take the speaker max rating (35 watts) multiply by the number of speakers and arrive at 350 - simple math. The KC configuration has two less speakers (no tweeters in the rear doors), therefore it must only be 280 watts. I am not really knocking Nissan here, most all the OEMs calculate audio power using similar methods. As a matter of fact most manufacturers of auto audio equipment can get very creative in their specifications - what you see is not always what you get!

 

If you want to explore the power of the stock RF amp a bit further, take a peek at the fuse value and apply P=VI. (power in watts = volts x amps)

350 watts divided by 12 volts would give a fuse of 29 amps, which would be the peak power before the fuse blew (not RMS).

350 watts divided by 13.6 volts would give a fuse of about 26 amps (peak).

And this is the input power to the amp, which functions at something less than 100% efficiency, so the power out to the speakers would be a bit less.

Now the actual fuse rating is not 29 amps or even 26 amps. I will leave it to the interested reader to calculate the actual max power to the RF amp.

 

So after reading eveyrones posts on the forum I decided to get everything installed by the installer rather than have the headunit installed first then the rest of the system myself. Thanks for everyones help.

So one more question now.
Here is my setup:
Eclipse 5495
McIntosh 4 channel MC-420M amp
2 x 6.5 MB Quart Q seires components
1 x 10" JL W3 sub in a sealed box
Run 2 channels to the front speakers and bridge the other 2 to the sub.

I asked the installer to just output the rear speakers from the headunit outputs and jump the stock amp because I just wanted some "filler" sound. He stated that i should bridge the rears with the front channels to bring it down to 2ohm and that it would sound much better. (he said the other way I would barely be able to hear it). I am more into the clarity/quality of the sound versus big booming loud sound. Just wondering if you guys have any opinions.

Thanks Again...

 

ok if you really want them..

MB Quarts have bright but Harsh Tweeters

You can't run a front and rear channel to the same speaker it will not work like that. Is he saying you can brige the amp on the HU? BTW the speakers should get more power since they are 2 ohm not less, what you risk hooking each to the same channel is stressing the HU too hard because there will be more current draw with less resistance. or is he saying to add them to theamp on the front channels, if I would not recomend that either since your fronts will be 4 ohms and the rears are 2 ohms. Plus then you can't fade front to back and you want your front soundstage to outpower the rear stock crap


You COULD wire both speakers in series to one channel and hook them to the HU. That is how I have my rears hooked to my Eclipse CD5444, one chanel powers them both about the same as the stock HU, maybe a bit less.

I still need to call eclipse to ask if the HU is 2 ohm stable or not.

how much power are you going to feed the 10?
I'd aim for min 300 RMS, hell even 400 watts RMS if you can get a decent size box, I hear W3V2's like a little extra power or u getting a version1?

Oh, yea why not install teh HU yourself? It's not very difficult.

 

I have had the mcintosh, mb quarts, and jl for a couple years so i am just moving them over from my old car. As for the harshness, they are very harsh but I just opened the crossovers and moved the jumpers for the tweeter down to take care of the harshness.

So the 2 front mb quarts will be on channel 1(left front) and channel 2(right front) and the JL 10W3 will be bridged on the channel 3/4. You are right about wanting the front sound stage being louder which is why I wanted to power the craapy rears off the headunit.

So your saying i should run the rears off one channel off the head unit to get it down to 2ohm, Correct?

As for the 10" Im not sure of the specs but I've had it installed before it hit pretty hard and clean. McIntosh amps are only rated at 100w bridged.

As for the reason i did not install it myself(this is my first time paying for an install of anything) is because eclipse will not give you the full three warranty unless you get it installed at an authorized dealer. So i took it there to get the headunit installed and they made me a pretty good offer to install everything...

ok if you really want them..

MB Quarts have bright but Harsh Tweeters

You can't run a front and rear channel to the same speaker it will not work like that. Is he saying you can brige the amp on the HU? BTW the speakers should get more power since they are 2 ohm not less, what you risk hooking each to the same channel is stressing the HU too hard because there will be more current draw with less resistance. or is he saying to add them to theamp on the front channels, if I would not recomend that either since your fronts will be 4 ohms and the rears are 2 ohms. Plus then you can't fade front to back and you want your front soundstage to outpower the rear stock crap


You COULD wire both speakers in series to one channel and hook them to the HU. That is how I have my rears hooked to my Eclipse CD5444, one chanel powers them both about the same as the stock HU, maybe a bit less.

I still need to call eclipse to ask if the HU is 2 ohm stable or not.

how much power are you going to feed the 10?
I'd aim for min 300 RMS, hell even 400 watts RMS if you can get a decent size box, I hear W3V2's like a little extra power or u getting a version1?

Oh, yea why not install teh HU yourself? It's not very difficult.

 

I have had the mcintosh, mb quarts, and jl for a couple years so i am just moving them over from my old car. As for the harshness, they are very harsh but I just opened the crossovers and moved the jumpers for the tweeter down to take care of the harshness.

yes that will help since you already have the wy not then right...

So your saying i should run the rears off one channel off the head unit to get it down to 2ohm, Correct?

No, this brings the load on the HU up to 4 ohms, However you will not have sterio sound in the rear and it kinda sucks, I know cause I have done it and I want sterio in the rear even if I can't hear it much! I'm going to call eclipse and see if the HU is 2 ohm stable if it is you will get alot more volume hooking each to a seperate channel.

As for the 10" Im not sure of the specs but I've had it installed before it hit pretty hard and clean. McIntosh amps are only rated at 100w bridged.

Might be a V1 then, does the dust cap stick out or is it inverted? McIntosh amps are underrated, 100 watts isn't going to pund a W3 at all hell I feed more to my W0's; but from that amp I dunno! You already had it so I'm assuming it sounded good before and thats why your keeping it.

As for the reason i did not install it myself(this is my first time paying for an install of anything) is because eclipse will not give you the full three warranty unless you get it installed at an authorized dealer. So i took it there to get the headunit installed and they made me a pretty good offer to install everything...

Yes they told me the same thing at goodguys, however, it was $50 to install the HU or I could buy a $60 5 year warranty through them so I figiured I would take the 5 year warranty and install it myself, this also avoids me having to make appointments should my HU fail I can jsut pull it myself. (good thing too case every time I wana change something or hookup another amp etc I have to pull the HU. Plus I don't think they calculated the cost for the XE Double din bezel or Metra install kit. There was a couple different ways to install these parts and so I was able to try them and pick the way I liked best. Make sure they give you ALL the screws back, HU, and CD Changer etc, I hope they have one f the star screw drivers cause thats what the factory crap uses. Also Make sure they don't turn the car on while the Airbag light indicator is unplug I heard it can cause the airbag indicator on the HUD to flash. Also tell them they had better not break any of the plugs controlls etc that have to be moved around.

Are you getting the Factory Bezel or the cheaper one?

 

I called eclipse and they told me NOT to hook 2 ohm speakers up to it because eventualy in the long run the HU will go into protection. The HU is not 2 ohm capable.

However I have a feeling the rep is incorrect since the Factory HU can drive these guys fine. I have a different model give them a call on yours. I won't be taking the risk, I will be running them in mono wired in series untill I can replace the rears with some coaxils

 

Might be a V1 then, does the dust cap stick out or is it inverted? McIntosh amps are underrated, 100 watts isn't going to pund a W3 at all hell I feed more to my W0's; but from that amp I dunno! You already had it so I'm assuming it sounded good before and thats why your keeping it.

It sticks out.

Yes they told me the same thing at goodguys, however, it was $50 to install the HU or I could buy a $60 5 year warranty through them so I figiured I would take the 5 year warranty and install it myself, this also avoids me having to make appointments should my HU fail I can jsut pull it myself. (good thing too case every time I wana change something or hookup another amp etc I have to pull the HU. Plus I don't think they calculated the cost for the XE Double din bezel or Metra install kit. There was a couple different ways to install these parts and so I was able to try them and pick the way I liked best. Make sure they give you ALL the screws back, HU, and CD Changer etc, I hope they have one f the star screw drivers cause thats what the factory crap uses. Also Make sure they don't turn the car on while the Airbag light indicator is unplug I heard it can cause the airbag indicator on the HUD to flash. Also tell them they had better not break any of the plugs controlls etc that have to be moved around.

That's a pretty good idea to get the warranty from good guys...maybe next time. I'll make sure ot ask for everything back. Thanks for the heads up.

Are you getting the Factory Bezel or the cheaper one?

I got the nissan bezel and a scoshce harness.

 

I called eclipse and they told me NOT to hook 2 ohm speakers up to it because eventualy in the long run the HU will go into protection. The HU is not 2 ohm capable.

However I have a feeling the rep is incorrect since the Factory HU can drive these guys fine. I have a different model give them a call on yours. I won't be taking the risk, I will be running them in mono wired in series untill I can replace the rears with some coaxils

Ok I just called eclipse and they said it would cause a problem and not to do it. They said the toyota systems that come with JBL systems had the same problems when trying to hook up a 2ohm speaker to the 4ohm out, so they assume it will be the same in a titan.

Also I read at the12volt.com that you should not wire a headunit in series because it causes too much internal load, im not familiar with wiring/bridging headunits but everyone there says it is not a good idea...

 

Ok I just called eclipse and they said it would cause a problem and not to do it. They said the toyota systems that come with JBL systems had the same problems when trying to hook up a 2ohm speaker to the 4ohm out, so they assume it will be the same in a titan.

Also I read at the12volt.com that you should not wire a headunit in series because it causes too much internal load, im not familiar with wiring/bridging headunits but everyone there says it is not a good idea...

Hmm I'm not sure it is a problem in our case, the stock HU puts out about 7 watts to each speaker. With the stock speakers wired in series the Aftermarket HU is putting out about 6 watts to each speaker. So whats the problem?

I have not had any issues so far but now you made me worried. I don't understand what the diference would be running a 4 ohm 12 watt speaker or

two 6 watt speakers wired for 4 ohms.

I don't know how many watts the rears really are I just know the faactory HU does not put out very many RMS watts to begin with so I' assuming eve with 2 speakers the load is not really anymore than hooking 1 aftermarket 4 ohm speaker to it.

Maybe you can post my question over there and look for an answer that is actualy convincing as to why in our case this would be such a bad thing.

BTW, my HU does heat up some in the rear cause I removed it once while playing for a long time, and I noticed, but it does not heat up the CD for front of the HU so I don't think it is anything excessive.