[Subw00er]

Anyone else have issues getting rid of the noise? I think my issue may be from the antenna ground.

I've tried many grounding points, and yes I've grounded the metal down, and yes I've installed in many cars. The sti is giving me trouble!

[008STI]

Hi, sorry to hear you're still having trouble. Where are your grounding points? Did you try this suggestion from tshrey:

On the engine whine issue, disconnect the ground from the headunit and run a wire back to the amp. Grounding the headunit and amp at the same point should resolve most problems; occasionally even with this step you can still get a ground loop through the shield on the antenna, but most modern head units have decent antenna isolation.

I found it in your other thread.

I notice whine sometimes when I connect my mp3 player through the aux inputs on the stock nav unit, fwiw.

Let us know if you find a solution!

[Turninconcepts.com]

I have a Avic D3 installed in my sti and have no issues with whining. I grounded it through the factory ground wire that normally attaches to the side of the radio mounts.

[Subw00er]

Originally Posted by 008STI

Hi, sorry to hear you're still having trouble. Where are your grounding points? Did you try this suggestion from tshrey:



I found it in your other thread.

I notice whine sometimes when I connect my mp3 player through the aux inputs on the stock nav unit, fwiw.

Let us know if you find a solution!

Ya I did run a 10gauge back. I still had the noise. I did notice that when I disconnected the antenna wire, the noise was much less. I was wondering about those antenna ground isolators.

[SLVR08STI]

Mine does it on the stock radio

[GilMikalian]

In my old car, the only way I got rid of the whine (and blinking headlights) was with a capacitor. I bought a 1 farad cap but you'll pobably get away with a 500 microfarad cap.

[MacAlert]

Caps do not get rid of the noise. The whine you hear is usually related to a grounding issue (not just the radio ground, could also be the grounds under the hood).

[GilMikalian]

Originally Posted by MacAlert

Caps do not get rid of the noise.

Looks like your experience is different than mine, but they did get rid of the alternator whine for me.

[MacAlert]

Originally Posted by GilMikalian

Looks like your experience is different than mine, but they did get rid of the alternator whine for me.

This is straight from my installer.....also, caps are worthless. You are better off upgrading the grounding points under the hood.

[jrdriller]

there are a couple of grounding points: one in the harness, and one for the radio chasis

[tshrey]

What kind of head unit, what kinds of amps, what is the signal path from the head unit to the amps (speaker level or line level). Let me know and I'll help you get this sorted out.

[tshrey]

Originally Posted by MacAlert

This is straight from my installer.....also, caps are worthless. You are better off upgrading the grounding points under the hood.

Caps are absolutely worthwhile if you know what you are using them for. Systems with large power supplies in the amps will usually attempt to draw current faster than a battery can supply during hard hits; a cap can discharge several orders of magnitude faster than a battery. If your lights dim when your subs hit a cap is needed.

The only way I can see a cap helping with alternator whine is if you alternator diode trio was damaged. If the alternator is healthy the whine is caused by ground points being at different potentials.

[tshrey]

Originally Posted by jrdriller

there are a couple of grounding points: one in the harness, and one for the radio chasis

That is for the factory head unit; I'm assuming he is using an aftermarket deck with amps. When going aftermarket neither one of these should be used, the head should be grounded at the same point as the amp.

[MacAlert]

Originally Posted by tshrey

Caps are absolutely worthwhile if you know what you are using them for. Systems with large power supplies in the amps will usually attempt to draw current faster than a battery can supply during hard hits; a cap can discharge several orders of magnitude faster than a battery. If your lights dim when your subs hit a cap is needed.

The only way I can see a cap helping with alternator whine is if you alternator diode trio was damaged. If the alternator is healthy the whine is caused by ground points being at different potentials.

I've been in my installers car. 3 amps, 2 12" subs, 8" midbass in the doors, 6.5" coaxs, ribbon tweeters, digital processor and absolutely no dimming of the lights. All he did was upgrade the stock grounding points and install an Optima battery.

[tshrey]

Originally Posted by MacAlert

I've been in my installers car. 3 amps, 2 12" subs, 8" midbass in the doors, 6.5" coaxs, ribbon tweeters, digital processor and absolutely no dimming of the lights. All he did was upgrade the stock grounding points and install an Optima battery.

Running how much power?

Optima gel-cell batteries are a large upgrade over the POS units we have as well. I'm not saying grounds are unimportant; current is a loop, you've got to be able to get it back where it came from. What I am disagreeing with is your statement that caps are unnecessary in general. They can and do make a difference IF your current draw exceeds your battery discharge capacity. I don't care if your grounds are directly welded to the car, if the power supplies in the amps outrun the battery the voltage drops.

I was an installer during college. I ran 2 Soundstream Reference 500's into a pair of Reference 12 subs (the rest of the system was McIntosh amps running B&W home audio drivers). Without the cap the lights would dim, and that was in a truck with a PAIR of Optima gel-cells.