Ok, just as the title says I got rid of my alternator whine. I've been having this issue with my 2008 EX Element when I decided to use aftermarket amps with the OEM head unit.

Heres a little background of my components and the way I installed it:

OEM EX headunit
Polk DB seperates for the front
Polk DB coaxials for the rear
JL audio 12W6 subwoofer
Rockford Power 4004 pushing everything

I followed the wiring diagrams shown in the stickys and soldered RCA plugs to the OEM harness after cutting off the green plug under the passenger side kickpanel that goes into the factory amp. I don't care what any of you say, but i'm never gonna use the factory amp again so it didn't bother me to cut the plug. Note: The factory headunit has a crossover built into it. In order to send low frequency signals to an amplifier, you have to use the subwoofer output from the factory headunit. The subwoofer channel had to be split into two channels to plug into the amplifier, therefore I had to turn the gain up to match the front and rear speakers. A metra factory amp bypass kit was used so I wouldn't have to run speaker wires to each of the doors.

I used two channels from the Rockford amp for the front and rear speakers and the other two was bridged for the sub. I lost the fade control, but that didn't bother me one bit, at least I got to retain the subwoofer control.

This setup had very bad alternator whine. I unplugged the RCA connectors from the amplifier and the whine went away, therefore this pointed me to the factory headunit.

To get rid of this all I did was order the N-555 from Navone Engineering, plugged it into the RCA plugs that send the signal to the front and rear channels and the noise was gone!! Woo Hoo. I didn't get one for the subwoofer channel since it wasn't making any noise. $38 fix.

Bad Ground! Text book is to go straight to the battery.

Ok, just as the title says I got rid of my alternator whine. I've been having this issue with my 2008 EX Element when I decided to use aftermarket amps with the OEM head unit.

Heres a little background of my components and the way I installed it:

OEM EX headunit
Polk DB seperates for the front
Polk DB coaxials for the rear
JL audio 12W6 subwoofer
Rockford Power 4004 pushing everything

I followed the wiring diagrams shown in the stickys and soldered RCA plugs to the OEM harness after cutting off the green plug under the passenger side kickpanel that goes into the factory amp. I don't care what any of you say, but i'm never gonna use the factory amp again so it didn't bother me to cut the plug. Note: The factory headunit has a crossover built into it. In order to send low frequency signals to an amplifier, you have to use the subwoofer output from the factory headunit. The subwoofer channel had to be split into two channels to plug into the amplifier, therefore I had to turn the gain up to match the front and rear speakers. A metra factory amp bypass kit was used so I wouldn't have to run speaker wires to each of the doors.

I used two channels from the Rockford amp for the front and rear speakers and the other two was bridged for the sub. I lost the fade control, but that didn't bother me one bit, at least I got to retain the subwoofer control.

This setup had very bad alternator whine. I unplugged the RCA connectors from the amplifier and the whine went away, therefore this pointed me to the factory headunit.

To get rid of this all I did was order the N-555 from Navone Engineering, plugged it into the RCA plugs that send the signal to the front and rear channels and the noise was gone!! Woo Hoo. I didn't get one for the subwoofer channel since it wasn't making any noise. $38 fix.


David Navone is god! Since he builds the product in his back shed with pride, he'll warranty all items for life.

I have posted this a million times but I will say it again. The Honda factory premium HU used in the E uses balanced audio (2 live signal conductors and no ground/shield). You can’t, as the original OP found out, connect RCAs to the HU outputs and plug in an aftermarket amp. The interface the OP used is a small transformer that performs a balanced to unbalanced conversion. The major problem with small transformers is really bad low frequency response and very high distortion. I build a 5-channel converter that uses high-end active amps that performs the same job with out the distortion and roll off.

You can also use amps that already have balanced inputs like the JL, 2008 Kicker Zx and some RF punch and power series amps.

There are other considerations for a high quality low noise install with the factory HU but I won’t go into it here. I build complete harnesses for the Civic and TSX that are plug and play and incorporates the necessary compensation for the HU output drive. I do not have one for the E yet because it uses a different connector. I do plan to do one in the future.

jeff

Million times? You have 13 posts. It seems your preaching after the original poster fixed his issue. The issue I found was that the stock h/u was passive in the fact that it's output wattage was not strong enough to signal an aftermarket amplifier. Hence why I tapped into an output after the stock amp with an LLC (Navone of course) and ran RCA output to a MRV-450 5 channel.

Yeah, Navone products are awesome!! I thought about using the signals after the factory amps, but heard that most factory amps distort the signal somewhat. I wanted to try and stay away as much distortion as I could so took the signal from the headunit. I'm thinking of getting either the JL cleansweep or the Rockford 360.1 to try and improve the signal.

All of this is why I just want to replace the door speakers with efficient aftermarket ones and be done with it. I don't want to lose the HU and all the workarounds are too expensive and complicated because I can't do them myself.

Million times? You have 13 posts. It seems your preaching after the original poster fixed his issue. The issue I found was that the stock h/u was passive in the fact that it's output wattage was not strong enough to signal an aftermarket amplifier. Hence why I tapped into an output after the stock amp with an LLC (Navone of course) and ran RCA output to a MRV-450 5 channel.

The stock HU produces a 4 volt balanced signal; it has plenty of “power” to drive any aftermarket amp. The real problem is that it is a balanced signal and most car audio amps are unbalanced (coaxial) inputs. The device used would not produce any “power” gain and in fact would introduce a small loss.

I have posted this information a lot albeit not so much on the E site. I have been building interface solutions for the Honda Premium HU for about two years and I have well over 30 years of audio and electronics design and repair experience.

Again, the reason the noise went away was because the transformer in the LOC looks like a balanced interface to the HU and provides an isolated ground for each input of the amp. It is a fine solution but you can get better SQ if you keep the signal balanced all the way to the amp and then use an active converter to go o to RCA unbalanced.

A million might be a bit much, but I do get a lot of PMs on the other sites about this very subject over the past two years.

jeff

Mercman,

If you'll pardon a naive question, would a balun work in this kind of application?