alternator noise

I have a few questions for you, Do you have an ohm meter, or access to one?   How loud do you have to turn your radio to reach your desired listening level?   You say the noise is very noticeable, am I to assume that it is way worse than any normal engine noise. What model is the kicker amp(s)?

I do have an ohm meter(fluke). I turn my radio probably about 2/3 of the way up. As far as the noise is concern, lets put it this way; when I listen to the radio about 1/3 of the way up I can hear the alternator whine more than the music. Even at 2/3 of the way up I can still hear it in the background. The kicker amps I have are an SX700.4 and an SX1250.1. I am also using their amp control unit that allows me to control them directly from my dash. I forgot to add in the last post that I have tried different grounds for the radio. I tried directly to the frame behind the radio and to a wire grounded in the same spot as the amps running in the same side of the rca's . Right now is connected to the last one mentioned before(factory nissans don't come with a ground in the radio harness at least in those years). I have even tried rca noise filters and that only made it worse. I hope this helps, I just don't know what else to do.

I am not at all familiar with the amp control module you speak of. Is it easy to disconnect that device to try and eliminate it from the possible source of the noise? Are the RCAs on the 4 channel amp somehow numbered, amp 1 and 2 and amp 3 and 4? AT the amp, because it is easier to get to than the back of the radio, I need you to unplug all of the RCA cables from both amps. Set your meter to the Ohms scale. Ground the black lead of the meter. Now touch the red lead to the shield of one of the RCA cables. Notice the reading. Repeat this for the remaining 5 cables. I am not familiar with the Eclipse unit either, but I am sure the reading should be no more than 110 ohms, on each of the cables. It should be closer to 15 ohms. But anything around 110 should be ok. If you get a really high reading stop and post your findings. If all appears to be OK there, Lets connect the RCAs back to the Amp 1 and 2 jacks of the amp. Start the car and see what happens. If amp is not labeled 1 and 2, Connect front first, then if still noisy remove them and try the rear. If you still have noise, kill the car disconnect the RCA cables. Now with the meter once again set to ohms, I need you to connect the black lead to one of the non-bridged speaker wires. (this is of course on the 4 channel amp) Once you do that just to make sure we have the correct terminal touch the red lead to each of the 7 remaining speaker terminals. You should get about 0.3 ohms on 3 of those 7 connections. If you do, you have the correct terminal. Now touch the red lead to the shield of the Amp's RCA jack. There should be no cable attached to the amp. You should get around the same .3 ohm reading, at least on the amp 1 and 2 jacks. Check all 4 and post the results. Nissan (as of 06) still does not put a ground wire in the harness or on the radio. Still gets ground through the chassis of the radio and their more than adequate radio mounting technique.

Had lots of earlier Maxis with no problems, could we have an under-nourished alternator or a bad battery? N.B. 10 Farads?