I put a cheap ebay double din head unit in my 2003 Porsche Carrera. It would not make any noise, so I found that I needed an adapter for the MOST fiber optic system that runs the amp. I bought that and indeed I now have sound. However, I have a very annoying alternator/engine noise coming through the system. So far I have tried significantly improving the grounding system and changing the power (b+) location. Right now I am using the cigarette lighter wire, which stays on all the time in this car. For an accessory wire I am using a small one that runs to the exhaust cutout system switch. I suppose this might be the problem but I doubt it, because to my knowledge the switch only disables the system.
I now have soldered connections almost everywhere, with the exception of the actual two power plugs and the ground, which I anchored securely (I believe) into the aluminum brace of the dash.
The MOST adapter is a little box with b+, acc and ground. The fiber optic plugs into the back, and has RCA plugs that go to the head unit. It only uses L/R plugs, so this system cannot fade.
Will RCA jack noise reducers work in my case? What else should I do?
I now have soldered connections almost everywhere, with the exception of the actual two power plugs and the ground, which I anchored securely (I believe) into the aluminum brace of the dash.
The MOST adapter is a little box with b+, acc and ground. The fiber optic plugs into the back, and has RCA plugs that go to the head unit. It only uses L/R plugs, so this system cannot fade.
Will RCA jack noise reducers work in my case? What else should I do?
E=carwhisperer;6225268]I put a cheap ebay double din head unit in my 2003 Porsche Carrera. It would not make any noise, so I found that I needed an adapter for the MOST fiber optic system that runs the amp. I bought that and indeed I now have sound. However, I have a very annoying alternator/engine noise coming through the system. So far I have tried significantly improving the grounding system and changing the power (b+) location. Right now I am using the cigarette lighter wire, which stays on all the time in this car. For an accessory wire I am using a small one that runs to the exhaust cutout system switch. I suppose this might be the problem but I doubt it, because to my knowledge the switch only disables the system.
I now have soldered connections almost everywhere, with the exception of the actual two power plugs and the ground, which I anchored securely (I believe) into the aluminum brace of the dash.
The MOST adapter is a little box with b+, acc and ground. The fiber optic plugs into the back, and has RCA plugs that go to the head unit. It only uses L/R plugs, so this system cannot fade.
Will RCA jack noise reducers work in my case? What else should I do?[/QUOTE]
As you have removed the factory headunit, could you just run speaker wire to the door speakers? The door panels come of easily on Porsche in general. Just dump the factory amp?
I now have soldered connections almost everywhere, with the exception of the actual two power plugs and the ground, which I anchored securely (I believe) into the aluminum brace of the dash.
The MOST adapter is a little box with b+, acc and ground. The fiber optic plugs into the back, and has RCA plugs that go to the head unit. It only uses L/R plugs, so this system cannot fade.
Will RCA jack noise reducers work in my case? What else should I do?[/QUOTE]
As you have removed the factory headunit, could you just run speaker wire to the door speakers? The door panels come of easily on Porsche in general. Just dump the factory amp?
No. It is in a plastic box and does not have provision for mounting per se. I do have it attached to the underside of the cupholder, which is aluminum but not grounded. It does have a ground wire and I am pretty sure I have it grounded pretty well.
Do you recommend the rca type ground loop isolators? This does seem to be worth a try.
Thanks for the replies. I bought an RCA ground loop isolator at Best Buy for $12. Besides the RCA plugs it only has two grounds. I also installed some of those magnet thingies that I took off of a printer cable on the RCA cords and the ground. I put it all together and it sounded good with the key in the ignition. But when I started the car no sound came out of the system, a problem that has happened at various times in this arduous journey. The HU lights up and is playing, but it won't make any sound. I suspect it could be the MOST adapter box or possibly a problem delivering power to the amp. That part of the system is still stock. Before I removed the stock Becker, it would stop playing sometimes. I think it was still lit up, but I don't remember for sure.
I had that problem with an amp, and no amount of ground this or that made any difference, as it was transmitted from the alternator. The amp was isolated from the car chassis as well from the start. The problem persisted with the rca disconnected, engine running.
What worked was a simple choke made from a ferrite core, and about a foot of the 10 gauge + wire that was used to power the amp.
What worked was a simple choke made from a ferrite core, and about a foot of the 10 gauge + wire that was used to power the amp.
No input connected would produce the noise, couldn’t see the logic in purchasing a ground loop isolator when there was no loop or differential between the signal ground and anything else.
The choke did the trick, is located near the battery. I can still hear a very faint whine, but hardly perceptible. That remaining low noise could be a ground loop for sure.
This was after putting a 5uf film cap right on the alternator, which helped in other ways, but not the whine so much, so there may be something to having both, but I hadn’t tried without the cap to verify that possibility.
I also had tried a dedicated ground cable to the battery, to the head unit, and other diode combinations to the chassis/head unit in various places. In the process I found a better source of power for the head unit, which was a bonus.
Found the choke recommendation on a 4wd, off-roading site for quieter CB radio operation.
The choke did the trick, is located near the battery. I can still hear a very faint whine, but hardly perceptible. That remaining low noise could be a ground loop for sure.
This was after putting a 5uf film cap right on the alternator, which helped in other ways, but not the whine so much, so there may be something to having both, but I hadn’t tried without the cap to verify that possibility.
I also had tried a dedicated ground cable to the battery, to the head unit, and other diode combinations to the chassis/head unit in various places. In the process I found a better source of power for the head unit, which was a bonus.
Found the choke recommendation on a 4wd, off-roading site for quieter CB radio operation.
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