pcaulfie

Installed my XM Commander unit with GLI and Line Driver with Aux-in. After intalling the Line Driver, I've noticed an increase in noise. Mostly when accelerating. I added some better (not great) RCA's and rearranged the mess of wires so their more organized. The increase in noise when accelerating is gone but I still have a high pitch noise that is more noticeable on talk stations.

Here's how it's wired:

Sat Receiver to GLI to Line Driver to RCA's to SNHOND adapter.

I tried putting the GLI after the line Driver but it made no difference. After reading some posts, my best guess is it's the ground for the Sat Receiver. I used the ground that's directly below the head unit and also appears to be the same grounding point for the head unit and/or nav. Maybe that's not the best place to ground? I read somewhere that that was a recommend place. Can anyone recommend another place?

Also, does the line driver have to be grounded? I noticed no difference when it was or wasn't. Thanks!

musicbox

Your noise could be alternator whine, just a guess don't hold me to it... Does the noise also get louder when in neutral and reving the engine?

Which line driver do you have?
Which GLI do you have (Radio Shack?)

Did you try it without the line driver and GLI ( and any combination in between?)

slo007

You should only need one (line driver or GLI). Not both.

What brand/model are you using?

pcaulfie

Interesting. Never thought of that. I'll give it a shot with the line driver only.

I'm using the RadioShack GLI and the Line Driver that Bass Mechanic has recommended, Turbo1. But I thought he used both?

No increase in loudness anymore after cleaning up the mess of wires and using better RCAs. It was very noticeable when accelerating at high rpms. Definitely was alternator noise. Now it's just a slight whine, but not as bad as it was.

slo007

I made a mistake. You should only need an LOC or line driver. Nevermind the GLI. It adds noise in most cases.

I had the same noise with a cheap GLI installed before my JL amp. I put a PIE LOC and most of the noise went away. I just get hic ups every now and then. I'm saving for a good line driver now.

I recommend discarding/returning the Radio Shack GLI.

Carter80302

Just had Circuit City install the XM Commander, using GLI and SNHOND adapter. The first day it sounded great, but today there is horrible alternator whine (very noticable when revving). I thought that by using SNHOND there would be no alternator whine--what did I do wrong?

pcaulfie

I think I'll do the same and save for a good line driver. The one I'm using is causing the noise. I tried powering it using different power sources and no change. Right now I'm just using the GLI and the noise is gone for the most part. Very slight at high volumes with no music being played.

I even went out and bought some quality rca's and if I just used those the alternator noise still returned.

slo007

The AUX adaptor doesn't isolate the noise. All it does is allert the HU to recognize there is an AUX audio source hooked up to it.

Sounds to me like the GLI unit you got is not up to par. You need something better.

gmfreed

Hey guys, I have the XM COmmander using the SNHOND3 and a good noise filter.......NO problems at all, no noise sounds great. My only issue is that the volume is just a little lower than cd's, but not a problem, somethingI can deal with rather than noise

pcaulfie

I can't handle the fact that I can raise the volume 100% and still not get the volume I want. No, I'm not deaf but I did install the Alpine Type S' in the rear deck. With the line driver and got a lot more punch out of the sytsem and it is noticeable without it. Of course I'd rather have low volume than high noise but will do some research to find a good line driver that works.

Bass Mechanic

the only simple way to solve all the issues you guys are having is to 1 get a line driver, 2
you need a GLI before and after the Line driver to rid yourself of the noise. my XM commander sounds every bit as good as the CD most of the time. i have 0 engine noise and all the volume of a CD.

some line drivers may help reduce or eliminate the noise but they would have to have a floating input and output ground on the RCA's most are common ground and will need a GLI

pcaulfie

So Bass Mechanic, I followed your recommendation of the PAC Turbo1 line driver for use with the XM Commander. You're recommending that I add another GLI so that I have one going in and out of the line driver? I've got the $15 Radio Shack one, so one additional should work.

One last question: Should I ground the Line Driver? I didn't notice a difference when it was or wasn't. Thanks!

Bass Mechanic

im using a RS GLI's like you have, if i had it to do over again i might consider getting a better shielded unit and somthing that doesnt have the filter at 1 end of the cable. this makes it hard to mount it away from the location of either the XM, the line driver or the SNhond3. it would have been nice to have the GLI in the center of the 3 or so foot cable its attached to.
having said that i had to add an extender to the GLI so i could place it in a location not near any of the stock wireing or it will pick up noise from anything electrical in the car.
i mounted the 1st GLI under the seat heater switch for the drivers seat inside the console.
the 2nd one i mounted to the right of the gas pedal behind the carpet. there is a nice little tunnel in there that i could have and would have preferred to mount both GLI's since there seems to be little to no factory wires, modules or anything electrical near it.

i noticed no degradion of signal using 2 GLI's which common sence tells me is a bad idea.

also your last question. yes you need to ground the Line driver if you use 2 GLI's because the instructions say to use the RCA ground for power but if you use one on both input and output you have essentially taken away any ground connections present to the Line driver so you need to provide a ground.
doing the install insures that each unit (XM,line driver, and SNHOND3) are not electrically connected in any way to each other. so no noise can be transferred.
however since a GLI uses a transformer to transmit the sound from 1 side of the GLI to the other any magnetic fields present will be transmitted into the signal path and therefore amplified.
so great care must be taken to make sure that where you put the GLI's must be at least 8-10 inches away fropm anything electrical or you will hear noise.

what i did was with the engine running and everything turned on and stereo at volume setting 30. turn the XM tuner off so there is no sound. any engine noise will easily be heard under this condition. as you move the GLI's around you will hear engine noise present when it comes too close to anything electrical. using theis method its much easier to find a permenant home to leave the GLI's while at the same time making sure there is no noise in that location. i would try near the gas pedal and if you need a short RCS extention to physically mount the GLI's in that location or any location that is free of noise.

pcaulfie

Ah ha, my GLI is installed right on top of the satellite tuner. I'll try your experiment, moving the GLI filter around and see if the noise clears. That would also explain why the noise was worse or not depending on the setup I used. Thanks for the tips. I'll give it a shot and see if it works.

elduderino

Yes, it's important to remember that a GLI has a coil in it, and coils can pick up noise when they are next to power wires. That *could* be it...

What kind of Line Driver do you have? You may need to give your line driver cleaner power - some of them don't have good input power filtering. You may need a power filter for your Line Driver.

If you don't have it grounded and it still works that means it's grounding through the RCA's... hmm.

pcaulfie

Ok, after doing without the line driver for a month I'm ready to try again. The line driver I have, for some reason, does not work anymore. Can't figure it out...oh well. Looking to buy a higher quality one and make sure I do this right. Any other model suggestions?

elduderino

Phoenix Gold LD22.