Are all noise filters created equal?

I picked up a 20amp noise filter from advanced, about 1 cubic inch in size. Then I stopped in at radio shack and found one that was still 20 amps, but it was more like the size of 2 decks of cards, and much heavier. I guess the only real way to tell if they work the same is to hook em up and test, but has anyone had any experience with noise filters and if one kind is better than the other?

What exactly do you do with this "noise Filter"?? Do you put it on you power wire?? Between you HU and amp on you RCA's?? Paul

well this filter connects inline with the 12v battery wire that powers the headunit. other than that, the only other thing I am gonna try is to make a new ground connection for the HU to see if that helps.   This engine noise/whine stuff has got to go. I tried the type of filter called a ground loop isolator that connects inline with the RCA plugs, but that had absolutely no effect. Also, I ran the RCA's outside of the car and it had no effect.

Have you tried to ground the amp and the HU directly to the battery?? Paul

danieljaluise wrote: well this filter connects inline with the 12v battery wire that powers the headunit. other than that, the only other thing I am gonna try is to make a new ground connection for the HU to see if that helps.   This engine noise/whine stuff has got to go. I tried the type of filter called a ground loop isolator that connects inline with the RCA plugs, but that had absolutely no effect. Also, I ran the RCA's outside of the car and it had no effect.

With this description of your issue, your noise is DEFINITELY coming from the deck. Did you use a harness, or cut the wires? Did you use a GOOD ground for the deck? Is the noise in radio only or CD too? Is the noise ever-present, or only when you turn on other accessories? We need a little more info... As far as the original question, the small one is an active noise filter, and they use a transistor inside (don't ask me how, I've never torn one open to look at the circuitry) to filter noise, and the big one from Radio Shanty is a passive one, using an LC network. I have seen in the past that both work, but I have had better luck with a high quality LC (big, heavy) filters. Just remember, ALL noise filters are band-aids, and only cover up the underlying problem. You really need to fix that, then you won't need a noise filter...It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

I did use a harness to intall the radio. I have previously had two different pioneer stereos in the car with no problem. The problem occured when I switched to the avic-n1. Someone suggested wrapping the wireing harness with aluminum tape. I might try that if I can find any, so far I have not been able to.

danieljaluise wrote: Someone suggested wrapping the wireing harness with aluminum tape. I might try that if I can find any, so far I have not been able to.

Don't waste your time... That will not fix anything. The issue is arising with the power supply in your car, possibly. I am referring to the ripple in the DC supply. Also, did you answer any of the above questions? If the noise only occurs with one source or the other, it is in the radio, and you may need to look other places to fix your noise problems...It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

I say swap the HU to isolate the prob. Swapping is the only way to diagnose a problem if you ask me. Don't get ahead of yourself.Tell the Snap-On guy I'm not here!

Alright. the noise occurs on all sources, even when the unit is off because the N1 keeps the amps running for some reason when all the sources are off. I guess it has to do with the navi voice guide or something. Anyway, the setup is loaded with accessories. A changer and 2 amplifiers (sat radio soon to come). It seems like infbaffle is onto something here. Without the amps, if i just run the speakers off the head unit, there is no buzzing. Only when I run the speakers from the external amps. Now I know it can't be RCA cables, because they are all run down the opposite side of the car from the power wire, and I tested it by running the cable outside of the car as well -still got the noise. I am going to try what infbaffle has suggested, and hopefully this will fix the problem. I will post what happens. By the way, I have used 3 amps, mounted in 3 different locations and 3 different ground connections, and all had the same noise. So that is why I really believe that even though the noise is only present when run through the external amps, I still think the noise is being generated by the HU.