Guitar Buzz/Humm-ground lift

Mark Lane · Post by **Mark Lane** » Mon Nov 13, 2006 1:08 am

Hi Guys,

When recording to ableton through my focusrite saffire to the laptop directly with a guitar, i get a buzzing when not touching the strings or metal on the guitar. Its like an electrical buzz. I think its a ground loop.

Was thinking of getting a DI box to plug between the guitar and the saffire, with a ground loop switch.

Anyone tried this and know if it works?

Cheers
Mark

Clearscreen · Post by **Clearscreen** » Mon Nov 13, 2006 1:52 am

There are three basic ways that hum and other power line-related noises can get into an audio system. One is through radiation in the air, such as when you bring an electric guitar close to the power transformer in an amplifier. In this case the guitar's pickup acts as an antenna that receives the 60 Hz. energy being radiated by the transformer. The whole point of using shielding to surround the center conductor on guitar wires and studio patch cords is to keep radiated hum from impinging on the wire inside the shielding.

unless you also get this sound when nothings plugged into the saffire it's probably not a ground loop. if you only get it when you're using the guitar it's probably the guitars pickups and you can try shielding em a bit more or using a noise gate (or maybe a denoiser?). what type of pickups are they? single coils pretty much ALWAYS have some noise in em unfortunately...

veggieryan · Post by **veggieryan** » Mon Nov 13, 2006 2:08 am

get a humx by ebtech.
its the only way.
works so good... buzz will go away 100%!

adhmzaiusz · Post by **adhmzaiusz** » Mon Nov 13, 2006 2:47 am

hey mark

the problem is usually caused by the magetic fields from your computer monitor going into your pickups...the best solution is turn your monitor off when you record, or step far back when ur ready to go

Mark Lane · Post by **Mark Lane** » Mon Nov 13, 2006 11:38 am

Hi Guys,

thanks for the input. thing is I have ruled out the guitar pickups because even though they are single coils (rickenbacker), i get the same result with my gibson which is humbucking.

i have also have a flat monitor on my laptop, not a CRT, which is why I believe that can't be the reason either.

I dont seem to have any problem with synths plugged into the saffire, only guitars. Like i say the noise goes away when i touch any metal on the guitar which makes me think it is a grounding issue.

It seems you can't get the HUMX in the UK. Anyone know of any UK equivilants?

Cheers
Mark

nolus · Post by **nolus** » Mon Nov 13, 2006 5:21 pm

Do you have a dimmer switch? if so turn it off or fully on. and If you have any low voltage lighting turn that off as well.

dimmer switches and low voltage lighting transformers are two of the biggest radiators of electrical noise.
and guitars are very sensitive.
get the best cable you can afford, and avoid long cables if possible.
A di box might help if the connection from the di box to the saffire is balanced line.

Contra · Post by **Contra** » Mon Nov 13, 2006 5:42 pm

nolus wrote: A di box might help if the connection from the di box to the saffire is balanced line.

best choice

Mark Lane · Post by **Mark Lane** » Wed Nov 15, 2006 12:42 am

Cheers for the input guys. Here were my findings:

The dimmer in my room DID cause buzzing and interference. So in almost complete darkness I went about elimnating the noise underneath that buzz. Which was a low level humming.

I noticed when I unplugged the laptop the hum went away. Which to me indicated a ground loop. What I couldn't work out was why I wasn't able to get this humming with my Korg EM1 connected to the saffire. perhaps because the Korg is mains powered I am not sure.

Anyway I stuck a DI box, a behringher Ultra G in between the guitar and the saffire and activated the ground lift. No luck at all with that, it didn't do anything!! Oh dear!

Soooo. Now I have a ground loop issue and some very mild interference underneath that. Now I can work off the battery of my laptop but I would like to have mains power really as I get a faster processor speed. So this is all a pain really.

I was wondering primarily how I can solve this problem. I was going to get one of these to plug the laptop into, which claims to filter out 58db of EMI/RFI noise. Will that do the trick?

http://www.dv247.com/invt/6322/

There is another one her that is more expensive
http://www.amazon.co.uk/gp/product/B...582572-9153414

Also a power conditioner strip from maplin, would this be better?

http://www.maplin.co.uk/Module.aspx?...er&do y=15m11

Any help would be appreciated as this has driven me mad!!

Back to the interference issue, as a side note, I have found that even an unplugged laptop has a mild effect on the low level buzzing I hear. So guitars do seem VERY susceptible to interference. It has never struck me to listen to it properly until the problem was this bad, but I am sure a lot of people are getting it and just don't realise. I am not sure whether you can get your guitars shielded against this sort of thing!

Cheers
Mark

hgavin · Post by **hgavin** » Wed Nov 15, 2006 8:09 am

Check out some of the advice in this posting, and the articles linked to by Martin Walker:
http://www.soundonsound.com/forum/showf ... ber=283773

Mark Lane · Post by **Mark Lane** » Mon Nov 20, 2006 5:23 pm

cheers mate, will do.

i think the problem may be the guitar picking up hum from the laptop mains adaptor. I will get my guitar shielded. a lot of the sound goes away if I touch the metal on my guitar.

forgie · Post by **forgie** » Mon Nov 20, 2006 5:39 pm

Shield your guitar. I shielded my Mex Tele with foil, and it cut down on 80-90% of the background "hum". It didn't get rid of all the "buzz", but it certainly helped.

I don't know what exact guitar you have, but if it has an internal cavity and a scratchplate, you can shield the cavity and back of the scratchplate with foil. Search around on the net for a better explanation - it definitely helps though.

Benoski · Post by **Benoski** » Tue Dec 05, 2006 8:20 am

i have the same problem, except i'm not using a noetbook but a desktop and my firewire solo is noisy as hell too. with no instruments plugged in! i open guitar rig and its noisy as hell

and it sucks to use the noisy reduction on gr because it just doesn't rule at all with it.

and because the firewire solo is powered by the pc and not the powersuply, i'm wondering if the ebtech hum x mama would work?

hope it makes sence. im sleepy

MrYellow · Post by **MrYellow** » Tue Dec 05, 2006 12:56 pm

adhmzaiusz wrote: the problem is usually caused by the magetic fields from your computer

Try turning around...... 90 deg to the field.......

Turn around slowly and you'll see the sound is only when the field is crossing your pickup.

-Ben

feyshay · Post by **feyshay** » Tue Dec 05, 2006 3:38 pm

If it is a ground loop, I don't think you'll get rid of it by changes with your guitar (or where you stand in the room). I'm sure dimmers worsened your problem.
You might have to have your laptop unplugged in the interim.
Do you have everything plugged into one power source? That sometimes helps. The HumX fixed this problem when I had it in a past rig. Too bad they don't make a UK equivalent.