Sign in with
Sign up | Sign in
Your question

Antec 900 Ground Loop (Front panel headphone hum)

Last response: in Components
Share
January 23, 2010 2:19:08 AM

I only recently started using the front headphone jack on my Antec 900 and started noticing a light but noticeable hum coming from my headphones. AFter some digging around, it looks like a common problem with Antec cases are ground loops. I dont fully understand how it works but in short, this problem causes the humming from the speakers. A quick google search netted me these two links:

http://www.incrysis.com/forums/viewtopic.php?id=29778
http://www.eggxpert.com/forums/thread/312283.aspx

Both of those links detail similar issues and a variety of fixes but none directly address the Antec 900 so I tried to fix it myself assuming the cases were built similarly.

To keep it short, I managed to get as far as the wiring for the front panel USB ports/microphone/headphone jacks but everything is enclosed in this small black plastic casing that looks like it can only be removed with a sharp object and brute force which would leave the thing demolished and unable to be repaired..leaving me with a mess of those wires.

I tried purchasing one of those Ground Loop Isolators and that dims the noise but doesnt eliminate it.

Has anyone ever successfully eliminated this Antec 900 ground loop problem? Any ideas on how I can? Any suggestions on an alternative method I cant take to get rid of it?

I have my 2.1 speakers plugged into the rear headphone jack and would like to use the front headphone jack whenever I game online and use ventrilo or teamspeak.
a c 144 ) Power supply
January 23, 2010 11:31:14 AM

I have three Antec 900 cases, and I do not have ground loop problems.

If you look up at the top of the front panel connections, you should have a double USB cable, a 1394 cable, an audio cable, and a 6 conductor ribbon cable. There should also be a single black conductor fastened to the top of the case. Do you have that wire?
m
0
l
January 23, 2010 12:09:41 PM

Yeah. I noticed that last night when I was taking it apart. Theres a single black wire coming from the front panel and is screwed to the top of the case.

One thing worth mentioning is that the ground loop hum gets lighter and lighter as I remove the front panel cables from the mother board. Without the 1394 cable and USB cable plugged in, the sound is very very light but then I lose my front panel connections.

Also, when I had it taken apart last night, I noticed the hum was gone and would only return if I touched that single black wire to the case. If it wasnt making contact, there was no hum. However, when I put the case back together, the hum was back regardless of whether or not that single black wire was attached or not.

Thats interesting about your Antec 900s. You have no humming from your front jack? Perhaps mine is defective somehow. I tried emailing ANtec last night but their online support page seems to be down.
m
0
l
Related resources
January 25, 2010 11:49:44 AM

I'm pretty sure this problem is present in all of the antec ##00 series cases. Maybe some people just can't hear it. I've done the same thing as you have and also got stuck not wanting to destroy the nicely packaged front panel connectors.

I found a thread for the antec 300 and it shows some pictures of the problem. They've got that chassis ground wire connected to the usb, 1394 & audio grounds so just removing the chassis ground still leaves 3 ground paths (further up the cable will still be shorting all of the connection's grounds together).

The only way I've been able to eliminate the problem so far is disconnecting the 1394, usb and the chassis ground which I have just taped off so it wont short to anything. I have a card reader with a front USB so that is working out for now.

Here's the thread with the pictures for the Antec 300: http://www.incrysis.com/forums/viewtopic.php?id=29778

In that thread he says something about using super glue to put the plastic case back together, but he never took a picture of it or even mentioned it before that so I have no idea if it has the same setup as the 900. If anyone can figure out how to pry that thing apart with an X-Acto knife or something that'd be great if they could let us know.

Edit: the link he provides in that post has instructions on taking the plastic thing apart!
m
0
l
January 25, 2010 12:45:29 PM

I noticed that too. The sound gets lighter and lighter as I unplug the other connections. I dont have any other front USB ports though so Id rather not go that route yet.

I dont see anything in that thread directly about taking apart that little plastic housing. It all sounds like he just forced it open. It definitely looks like it can be cut with an Xacto blade or a small pair of scissors but Im not sure how close the wires are bundled in there and I cant be sure that Im not cutting them as well. Ill hold off on this for a bit.

I also finally managed to get an email into Antec support about this. Ill see what they say. If they have a fix, Ill try that.
If they opt to send me a new front panel housing, Ill check that out in my case and see if they humming goes away. If it doesnt, Ill at least have a second hosuing to crack open and screw with without having to worry since Ill have another to fall back on.
m
0
l
February 1, 2010 3:01:04 PM

Small update:

Antec responded to my request this morning and asked for my address. Theyll be sending me a new front panel assembly and are claiming that this will solve the problem.

Once I receive it, Ill install it and see if the problem is fixed. If its not, I will dissect the old one following the guides in those other links in this thread and see if I can get rid of it that way.
m
0
l
February 12, 2010 6:21:55 AM

I have the same problem, the "ground loop" sound. Please tell us, when you have istalled the new front panel assembly, if it solved the problem..

I´m going crazy here!

/DaBone
m
0
l
February 15, 2010 11:19:06 PM

I got the replacement front panel assembly in and it didnt do squat. Same noise was there.

However, I did rip apart the extra assembly I now have and messed around with it. I didnt know which cable was the ground wire so I took a gamble and cut the black wire, taped off both ends, and then taped up the assembly real good. The ground loop is completely gone now. Be warned, however. The front panel sound is now mono only. It will not play stereo.

That wasnt a big deal for me since Im only using it for ventrilo, teamspeak, skype, etc but if care about having stereo sound on your front panel, do not do what I did. And if you do decide to, Id contact Antec first and have them ship you out a replacement to screw with. That way you always have something to fall back on if you screw up.
m
0
l
February 17, 2010 9:02:45 PM

jedwards16 said:
I got the replacement front panel assembly in and it didnt do squat. Same noise was there.

However, I did rip apart the extra assembly I now have and messed around with it. I didnt know which cable was the ground wire so I took a gamble and cut the black wire, taped off both ends, and then taped up the assembly real good. The ground loop is completely gone now. Be warned, however. The front panel sound is now mono only. It will not play stereo.

That wasnt a big deal for me since Im only using it for ventrilo, teamspeak, skype, etc but if care about having stereo sound on your front panel, do not do what I did. And if you do decide to, Id contact Antec first and have them ship you out a replacement to screw with. That way you always have something to fall back on if you screw up.


Ok. thanks for the reply! I will contact Antec for a replacement and try myself..
m
0
l
February 23, 2010 1:18:25 PM

Hello again
Have received a reply from Antec and they want a copy of my original proof of purchase(must include in the e-mail).
I'm not so good in English and therefore wonder what they mean.
Is it the sales receipt or anything else they want?

I checked on this page and even more confused.
http://en.wikipedia.org/wiki/Proof_of_purchase
m
0
l
a c 248 ) Power supply
February 23, 2010 1:43:59 PM

Yes, Your sales receipt is the proof of purchase. You will need to have it scanned and attached to the email per Antec's instructions.

The UPC bar code on a package is scanned at a cash registed when one purchases a product. Customers usually send it in for mail-in rebates. No need to to worry about that.
m
0
l
February 23, 2010 3:47:51 PM

JohnnyLucky said:
Yes, Your sales receipt is the proof of purchase. You will need to have it scanned and attached to the email per Antec's instructions.

The UPC bar code on a package is scanned at a cash registed when one purchases a product. Customers usually send it in for mail-in rebates. No need to to worry about that.



Ok. Thanks for the reply.

Do you think its possible to use a digitalcamera and take a photo of the receipt, instead of using a scanner?
Have no scanner and do not want to buy one..
m
0
l
a c 248 ) Power supply
February 23, 2010 3:50:34 PM

I think it would be okay as long as the image is a close-up and legible.
m
0
l
!