are rca connections grounded through amp/hu

[beatinpearls]

Do amps and head units ground rca connections to the chassis via the amp/hu ground? I would assume not cause using multiple amps and a head unit would introduce a ground loop. I am more familiar with home audio in this respect but not sure with car equipment.

[reedal]

Do your RCA's have an external ground wire...? Mine don't. Where else would the ground for them be?

[beatinpearls]

In home audio, not all components have a 3 pin power cord. For example, my blu ray player does not but my receiver does. Any DC or noise from the player is grounded by the receiver via the rca. If both components had a 3 prong power wire that would cause a ground loop. I read in the sticky about speaker whine that only the hu chassis should be grounded to prevent ground loops. So that pretty much answers my question.

[reedal]

Oh ok. I didn't know that. Haven't messed with home audio yet really. I didn't mean it to come off as a dick. I realized that's how it sounded after I read it. But yes, in car audio, the outside shield of the RCA grounds to the chassis of the HU/amplifier. The pin is the positive that transfers the signal. I would like to play with home audio, but that's not going to be for a while.

[Jhunt94]

depends on the type of RCA's needed, this might explain a little

[beatinpearls]

Jhunt that was perfect. I wasn't aware there were 2 different types of amplifier inputs. I am currently chasing a different issue but while I got things apart and was doing research this question came to mind. I am using a coax cable which is fine in home unbalanced components that drain noise caught by the shield to the wall ground in 3 prong power cords. I know you shouldn't have more than one component doing the drain as you end up with a ground loop. I wasn't sure if car amps did the same thing via the amp power ground. Either way thanks a ton for posting the video. As the "speaker whine" sticky said, only the hu chassis should ground the audio signal.

[beatinpearls]

No worries reedal. I started in home audio and most of my research has been in that area.

[beatinpearls]

So i checked all my RCA connections with a DVOM and guess im in the 75% of consumers and only my HU has grounded RCAs.So this raises a couple questions.

Im using Quad shield RG6, in my research of the pros/cons of using coax vs twisted wire, most people use the latter. Unless they have done well to keep their RCAs away from power wires, how do they not have noise? Since one wire carries the signal (unshielded) and the other is the drain wire, as usual.

I had forgotten but differential amps are the type used in professional or high end home audio that use balanced XLR 3 connector wiring. How do car audio systems use balanced signals on a 2 conductor wire unlike the XLR in other applications?

Also, are there HUs that send an inverse signal (balanced) output?

[RooTxBeeR]

That is the video of all videos explaining the matter. I always forgot how to find it when I want to though hahaha. In for answers to your questions.

[Bump4life]

thats why when solving noise issues, your source should be grounded to same point as amplifiers or any other device in path of RCA.