A Little Help with Ground Noise?

Problem is, i think i found a solution a few years back. But this year i;m trying to get back into recording.

So… guitar - direct into soundcard (PreSonus FireStudio Firewire) and then into Cubase7.
But always a very obvious hum, unless i touch the jack, or the pot, or the pickup.

This happens on all 12 of my guitars. And my most expensive cables do the same.

One solution would be to have someone touch the jack while i record. But thats absurd.

Ive already tried switching most things to run through a 2-pin plug adaptor, but no joy.
The cables from my soundcard output to mixer are balanced TRS.

Sorry i didnt know where else to post - but i’m sure this is an easy one.

Aloha T,
Can be sooo many things but a shot in the dark here.

Any AC wall dimmers close by?

If so, try turning them either all the the way down
or all the way up.

Good luck!

Another approach would be to post your question in the
‘Computer / Studio Hardware & Setup’ forum.



Your problem is due to a bad (or lack of) a good earth. When you touch the screen of the jack, you are earthing the system, so you need to get a good mains earth in the system, which can be tricky with things running from AC adaptors which don’t offer any earth.

Check you have a good screened firewire cable - this is the most likely cause of losing the earth - that is of course assuming that the computer itself has a good earth.

As long as you know what you are doing - you could take the mains earth and connect that directly to the earth of the jack lead - but I would check the computer has a good earth and use a screened firewire cable.

I like to record guitars sitting on a rotating stool. I’ll find the proper “limited hum” position and go with it.

Single coils are always worse, of course.

Are you running everything off the same grounded source?

OK, i think this situation is a nightmare for all self-recording guitarists. Yet, i’m sure i fixed it before - but that was in my old apartment.

I have tried many options now:

  • 2-pin plug adaptors.
  • All lights switched off (no dimmers here anyway).
  • 6-pin to 4-pin Firewire cable ( i recall this being a previous solution).
  • balanced cables (soundcard to mixer).

Everything is running off 2 Power-strips (i think you call them “Surge Protectors”). One plugged directly into the wall, and the 2nd Power-strip plugged into the first Power-strip.

Will buying an expensive “Power-Strip” help?

And how do you check if you have a good Earth?

Some of the better power strips will have this feature built-in.

Since when you touch your guitar jack, the hum
is greatly reduced;
how about a lil old school ‘afro-engineering 101’?

A long wire with alligator clips on each end.
Clip one end to your guitar and the other to your mixer/sound card
to complete the ground.

Very kludgy but might work.


Well, i’ve disconnected everything.
Guitar > soundcard > Monitors

Also removed the firewire cable.
The hum is still there.

Luckily, with my Tele’s, as soon as i touch the strings the buzz goes away. My Les Paul (copy) must have plastic hardware - i used DIY crocodile clips going from my torso to the Les Paul jack to eliminate the buzz. I just wont use the LP for recording.

As soon as i pull the cable out of the guitars - the buzz also dissapears.

Guitars are terrible creatures.

TGD said

Luckily, with my Tele’s, as soon as i touch the strings the buzz goes away.

Unfortunately this is normal. It’s the price you pay for playing the best guitar ever :sunglasses: but the Tele is picking up radio frequency from somewhere. Televisions, motors, fluorescent tubes, CRT monitors, dimmer circuits, fish tank oxygenation motors, overhead electrical pylons… I’m surprised your Les Paul has the same problem though. Is your monitor flat panel or CRT? If it’s CRT turn it off and see if the buzz goes away.

PS the fact that your guitar stops buzzing when you touch the strings means your system is earthed, as strange as that may sound.

Star ground is one possible solution. Getting a tester to check if the outlet is wired correctly is another.

I have fairly good success using anti-static bands. I use this one in particular:


I put it on the guitarist’s strumming arm and clip it somewhere on the guitar out of the way. Sometimes to the springs behind the bridge, the bridge itself… Sometimes I unscrew the cap on the guitar patch cable and clip it to the sleeve solder joint because it will not clip around the jack case (too big for the alligator jaw. Whatever works the best.

I have found that hum on laptop systems can be significantly greater to that of desktop systems, in part this also can be due to the power-integration to the audio interface.
At some sites/venues this hum can even be worse, depending on the quality of the power and how the circuits are grounded. - … someone also mentioned to me that you can have too many grounds in a system too?
I have (many years ago now), made myself a very simple cable that is always in my kit bag, which is suitable for my windows laptop I carry around, I basically soldered together a cable (using some standard MIC cable), with the following plugs terminating the ends: a [9-pin D sub] and a [1/4 " stereo Jack], and I ONLY have the shield(or outer sheath) soldered and connected to the 9-pin D-sub SHELL {ie no soldering to any of the 9pins} and at the other end to the ground part of the 1/4" jack.
I use this cable when hum is excessive, and plug the 9pin into the serial-port on the laptop (OK you can tell how old this laptop is now …), and I connect the 1/4 Jack end into usually a headphones input-jack on a Mixer (or AMP), and have found that if the mixer/amp is mains powered (no wall warts), WITH an earth pin, then 99% of the time, 99% of the hum goes too .

There is this trick that sound like a joke but sometimes does the trick. It’s completely free and if it works it works. Anyways! All you need to do is to flip the mains connector 180º … yes, like that! Pull the plug out, turn it half a turn and then plug it in again. It has worked for me a handful of times. Not that I’ve run into hum problem like the TO too often but it’s worth a try. I’ve heard it from others as well. I felt like a complete clown first time I tried and thought I won’t tell anybody that I tried something this stupid :confused: :blush: :laughing: . BUT THEN IT WORKED!!! so I’ll tell you now. Worst thing that can happen is that your problem is of another kind and then it won’t work. It’s still free. :sunglasses:

Does anybody have a technical explanation for this?

OK, I am on this, so many things. First off, the best solution: Use an amp and a mic.

#2) Do you have LCD monitors? The CRT monitors will induce hum, obviously. Dimmers have to be turned off, as was mentioned. This may not be your problem at all but just sayin.

3#) The Les Paul you have is of an era that did not use a typical grounding wire off the strings. They did this in the late 70s for a few years and then decided this was a bad idea. You can quickly check this with an digital ohm meter. The point here is plain, if the Tele stops when you touch the strings and the LP does not, then your LP is not grounded via the strings. For that matter, the HBs in the LP would be resistant to most RF and magnetic fields, so the noise you are complaining about is definitely 60 cycle ground buzz. Anyway, you can have this fixed in the LP by any competent luthier and I urge you to do this. I have fixed/rewired at least 4 LPs that buzzed their entire lifetimes, with the owners amazed and incredibly grateful to suddenly have their guitar behave normally. :slight_smile:

#4) The wrist bracelet shown is something I tried when I used the amp to speaker out to speaker simulator to interface - and it worked - but honestly, I never got as good a recording as I do using a mic on a cab. (Your path is different, yes, but I’m pretty sure the buzz was very similar.) Sometimes the late at nite thing is necessary but here I would suggest a PODxt or something similar.

FWIW, it seems very clear that the interface is not geared to accept a guitar, but I don’t know much about this device. Typically a guitar into any interface will need a different gain structure and input path. (On my Mackie, for example, they have two channels built in that have an option to use a guitar in direct if you want. It works well, no buzz.) If you did find a solution to this problem years ago, well, it remains to be seen how good that fix was. I say pursue another path. A good recording of a guitar is priceless to a track, IMO. :slight_smile:

When you turn the volume down on the guitars, the hum disappears?

If so, it is in the air and as someone else suggested, you may have to move around the room and spin around to find the quietest place. Try the static band too if you can. The static band has saved my butt a number of times.

Here is a little story. All my studio circuits are isolated and on the same phase in the electric panel. Last year, or maybe the year before that, I was picking up a hum from a dynamic mic, a ND 868, as I was recording an acoustic bass guitar. It was really strange and blew my mind. A dynamic mic picking up a hum, right? What I found was there was a CFL bulb in an outside light that stays on all night long that was causing the buzz. The bulb was 30’ away. I’m not sure how the noise got to the mic. It may have been in the air or back through the main electric panel. Since then, I was turned onto one of THESE. The wand lets me listen to RFI coming off things like amps to determine where a hum or buzz is coming from. Then I deal with it if I can.

So the rfi you are picking up may have nothing to do with you or your gear. It may be coming in from the main electric, even outside from a street light.


Conditioner may help, Did for me Check out the Tripp-Lite LCR2400 http://www.tripplite.com/en/products/model.cfm?txtModelID=2832