findasong
Hi,
i have 2 pc's almost side by side and one sound card per pc. One pc has the maya 44 usb and the other has the ag gigaport sound card.Both sound cards connect to an external mixer. My question is why is it that when both soundcards are connected, i get interference noise and when one card is unplugged, i get no interference.
By the way this has nothing to do with the software.
Thanks
i have 2 pc's almost side by side and one sound card per pc. One pc has the maya 44 usb and the other has the ag gigaport sound card.Both sound cards connect to an external mixer. My question is why is it that when both soundcards are connected, i get interference noise and when one card is unplugged, i get no interference.
By the way this has nothing to do with the software.
Thanks
Posted Mon 28 Apr 08 @ 9:09 pm
DGee
Hey,
It sounds to me that you may be having a ground loop problem. This is caused by the power supply of one of the laptops not being the same phase as the other one. Here are some things to try:
If one laptop has a three prong grounded power plug, use a 3 prong to 2 prong convertor plug to remove the ground.
If doing the above gets rid of the problem but not quite, reverse the 2 prongs in the power socket. Unplug the plug and put it back in but rotate it 180 degrees. If the plug is polarized, you may have to file down the bigger spade to fit.
If the laptops can be battery powered for a test, remove one of power supplies from one of the laptops and see if that makes a difference. If it does, then you most likley have a ground loop problem.
If the power supplies only have 2 prong plugs, try reversing one in the power socket 180 degrees. You may have to file the spade down a bit if it is polariized.
If this is not the kind of noise you are talking about, maybe try separating the laptops to see if that solves any issues.
I can't plug my laptop with it's grounded cord into my system. I get this terrible buzz although it is not a 60 cycle buzz. It is in the system no matter what the mixer fader is set at. I have to use a 3 prong to 2 prong convertor before it will work.
Good luck with your problem.
-DGee
It sounds to me that you may be having a ground loop problem. This is caused by the power supply of one of the laptops not being the same phase as the other one. Here are some things to try:
If one laptop has a three prong grounded power plug, use a 3 prong to 2 prong convertor plug to remove the ground.
If doing the above gets rid of the problem but not quite, reverse the 2 prongs in the power socket. Unplug the plug and put it back in but rotate it 180 degrees. If the plug is polarized, you may have to file down the bigger spade to fit.
If the laptops can be battery powered for a test, remove one of power supplies from one of the laptops and see if that makes a difference. If it does, then you most likley have a ground loop problem.
If the power supplies only have 2 prong plugs, try reversing one in the power socket 180 degrees. You may have to file the spade down a bit if it is polariized.
If this is not the kind of noise you are talking about, maybe try separating the laptops to see if that solves any issues.
I can't plug my laptop with it's grounded cord into my system. I get this terrible buzz although it is not a 60 cycle buzz. It is in the system no matter what the mixer fader is set at. I have to use a 3 prong to 2 prong convertor before it will work.
Good luck with your problem.
-DGee
Posted Mon 28 Apr 08 @ 10:04 pm
findasong
Thanks for the tip but i use desktops and not laptops, do you think this may still be the issue ?
Posted Tue 29 Apr 08 @ 6:12 am
DGee
Hey again,
Well it is something you should check on for sure. Do the 3 prong to 2 prong convertor trick on one of the computers and see what happens. I had this happen to me at work a while ago. I was setting up a mixer and digital recorder at the back of an auditorium and taking a feed from the onstage sound system. When I plugged the gear at the back into a wall socket, I got a hell of a racket. I had to find a short extention cord, cut off the grounding pin, then plug everything back in again. Solved the problem, no noise.
Give it a try, it might help. If not, then you don't have a ground loop issue and something else is causing the problem.
-DGee
Well it is something you should check on for sure. Do the 3 prong to 2 prong convertor trick on one of the computers and see what happens. I had this happen to me at work a while ago. I was setting up a mixer and digital recorder at the back of an auditorium and taking a feed from the onstage sound system. When I plugged the gear at the back into a wall socket, I got a hell of a racket. I had to find a short extention cord, cut off the grounding pin, then plug everything back in again. Solved the problem, no noise.
Give it a try, it might help. If not, then you don't have a ground loop issue and something else is causing the problem.
-DGee
Posted Wed 30 Apr 08 @ 9:17 pm
findasong
hi,
just wanted to give you an update.
It was not my power cord that was the problem because i cut out the ground prong and even reversed the plug.
The problem was strictly audio so i bought 2 loop ground isolators with rca cables at circuit city as someone had suggested in an early topic and that soldved the problem. It cost me $22 a piece.
Thanks for all the help.
just wanted to give you an update.
It was not my power cord that was the problem because i cut out the ground prong and even reversed the plug.
The problem was strictly audio so i bought 2 loop ground isolators with rca cables at circuit city as someone had suggested in an early topic and that soldved the problem. It cost me $22 a piece.
Thanks for all the help.
Posted Thu 01 May 08 @ 10:38 am
Tear Em 'Up
findasong wrote :
i cut out the ground prong
Please, please, please do not do that! It could cause you harm, or a fire! Cutting the ground off your cables is never suggested, nor recommended by VirtualDJ.
Posted Thu 01 May 08 @ 10:45 am
findasong
anyway it was just a test on a spare wire but after that test i put back the original wire back.
Posted Thu 01 May 08 @ 10:48 am
DGee
Hey Again,
Good job on the convertors. It still proved that you had a ground loop problem somewhere. One more thing to try, just for the heck of it, would be to make up a couple of custom RCA cables between one of the sound cards and your mixer that do not have the grounding shield attached at one end of each cable. This would remove the offending ground loop out of the picture. This is basically what the convertors do using cheap transformers. It would be intersting to see if this also solved your problem.
For the record, I do not recommend removing grounds from equipment either, but for testing purposes it can certainly show you where your problem lies.
-DGee
Good job on the convertors. It still proved that you had a ground loop problem somewhere. One more thing to try, just for the heck of it, would be to make up a couple of custom RCA cables between one of the sound cards and your mixer that do not have the grounding shield attached at one end of each cable. This would remove the offending ground loop out of the picture. This is basically what the convertors do using cheap transformers. It would be intersting to see if this also solved your problem.
For the record, I do not recommend removing grounds from equipment either, but for testing purposes it can certainly show you where your problem lies.
-DGee
Posted Thu 01 May 08 @ 10:59 pm