Why does my guitar hum... damn it!!

[gjm]

It seems like its been an age for me sifting through gear and software trying to sort out what it is I need to do the job I want and not loose heart. I am pretty happy with most things, but today I found another chink in the setup that I want to fix, possibly the last one of significance. I am very happy with my Macbook, my Alesis iO/14, Live 6LE, my Axiom 49, my Rode NT2000 and my classical guitar.... but NOT the hum I get when I plug the guitar in.

My guitar is nothing fancy. Just a entry level Greg Bennet/Samick cut away classical with a pick up. Two things happen when I plug my guitar in and make ready to record an audio track.

1. There is a distinct audible hum that gets louder when I turn the volume up, or increase the gain.
2. When I touch either the sound card or the end of the patch cord plugged from the sound card to the guitar, the hum instantly drops, almost dissapears.

Now when I plug the NT2000 mic in and record an audio track, everything is fine.

So my guess is that there is something about the guitars pick ups that are not right. I have a selection of guitar patch cords that all produce the same result. Could this be right? Is there something else to check or think about?

Cheers.

[logic_user99]

Have you got a) a hallogen or energy-saving lightbulb in the room, and/or b) a dimmer/switch? As it will be a piezo pickup in the guitar, either of those external factors can effect it.

The single-coils in my Telecaster are real suckers for noise & 'hum' when there's iffy lightbulbs or circuits around.

[SubFunk]

instrument audio signal connections are never balanced no matter if it is a fancy or non fancy instrument (because of the age they came up, there was not such a thing as balanced connex yet at all)

one trick is to use a DI box with a groundlift (they all for that reason have a groundlift switch) but don't use a cheap shit like behringer, go for something like BSS or Klark Teknik, it's well worth it, also logic_user99 is right that in most home situations you got not different earth ground points for light and sound... that way a light bulb or dimmer, etc. can cause a headache.

from what i can read a decent a DI box with a groundlift switch will solve your problem.

[chris vine]

Yes this is an infuriating problem that I also have had to deal with.

There sounds like there is a ground problem.

First off you probably need to get your guitar properly shielded. This site: http://www.guitarnuts.com explains all about the problem and shows how to seriously shield the axe.

The other problem could be in your AC setup - is it grounded?

The DI box groundlift trick might or might not work and will not fix the problem. Another trick like that is to use a wireless system for the guitar -

[the_antagonist]

is it because you never wash it?

[the_antagonist]

if you don't get it just forget it

[onehandstand]

i had a similar problem. it did go away by changing macbooks power supply to a grounded one

[LoopStationZebra]

Guitarnuts is such a great site. There's a lot of excellent tips there.

In a pinch, I've been known to use a simple gate that will cut down on the hum. At least in those moments between notes. Something to consider until you get that puppy lined with tinfoil.

[aizo]

I was recording a bass directly into my 828 last year. I don't own a bass so I borrowed it from a friend. Just a cheap no name bass. I thought...shit this is a real piece of crap. it hummed like hell. I was sitting on the floor with the pickups about 2 feet / half a meter away from the 828. for some reason i had to get up and walk to the other side of the room(which is not very big) the hum went away....i was like wtf? but it sounded great after that. i got an amazing bass sound from this pawn shop brand and finished my song.

try that....

[gjm]

Thanks folks. Lots of things to work with now.

Cheers.

[ethios4]

+1 to the DI box. Fixed my hum problems.

[forge]

well the other guys have already made some good suggestions with the hum, but I'm going to go one step further and say - mic the thing! your Rode Mic would probably get a much nicer sound than the pickup

I've never liked recording pickups - they are for Live use IMO

[gjm]

i had a similar problem. it did go away by changing macbooks power supply to a grounded one

This was the solution. Thank you.

[Patch]

Your guitar hums???

Hmmm... Mine gently weeps.

[UKRuss]

Badum tish.