Recording live guitar.

Hi guys, bear with me I’m new to this and old!
Whenever I record any of my guitars, be they electric or electro-acoustic I get a tremendous amount of background buzz!. I am using a Yamaham UR-12 audio interface. However, when I unplug my mains lead on my laptop and run on battery power it disappears. Why is this? And, how do I run with the mains connected and no buzz?
Thanks

That is probably being caused by an Earth Loop. What you may need to do is to use a D.I Box with an earth lift switch.

Does moving the lappy power supply further away from the guitars make any difference?

If it was just one guitar, I’d say it would be a disconnected earth wire inside, but since it’s more than one, I’d suggest the jack to jack might be the culprit. With the earth broken, there might still be a signal, of sorts but it would be horrible quality and full of hum. cable definitely plugged all the way into the socket at both ends? Try with a different cable.

Alternatively, and only if you have more than one piece of mains powered equipment in your rig you may have an earth loop. This could cause a hum when the lappy is plugged into the mains and not otherwise. The quick solution is to remove one earth cable, but please don’t do that unless you have a completely clear understanding of what you are doing. Equipment must be earthed for safety against possibly lethal shocks. If in any doubt at all, find someone local who is used to audio equipment who can troubleshoot the problem. One thing you can do which is good practice is to make sure all mains units are plugged in close together, not scattered across lots of sockets around a room.

Good luck, but proceed with caution.

Agree with AndyRH a DI box ground lift switch is a safe solution if you have one.

Hi!

Can I jump in to this thread with a similar question? Hope you don’t mind… But if you do, just let me know!

I have similar problem when playing a bass guitar (it’s a Rickenbacker bass guitar) when sitting infront of the computer and recording the bass guitar DI’d directly through my audio device (Steinbergs UR44) into my Cubase 9.5 Pro, then there’s some low signal… a “hum” or whatever such signal is called? But when I move away from the computer, let’s say 2 meters that “hum” disappears or at least gets noticable lower… It’s not a very annoying “hum” or signal but still… it can be conflicting with the over-all mix in the end, I guess… But this doesnt happen when I for example record a Gibson Les Paul guitar through my audio device as a DI recording into Cubase and also sitting close to my computer. So I guess it’s the bass guitar?

Anyway, my question, and as a solution (since I read this main post & the replies) is, if buying a “Tech 21 Bass Driver DI V2” (Url: https://www.thomann.de/se/tech_21_bass_driver_di_v2.htm) would remove that “hum”? It has a “Switch: Phantom and Ground Connect XLR”. Would that be enough to remove that hum?

Thanks for any reply!

Regards from, Robin Gardner

Robingardner, the hum issue you are having is due to the different pickups you have in your Rickenbacker and the Gibson.
The Rickenbacker pickups are single coil and they are causing interference, whereas the Gibson has double coil “Humbucker” pickups which, as the name suggests, reduces hum.

As for your suggestion for DI box, I think it’s a rather expensive choice and there are much cheaper boxes available. For example the one I use is a Behringer Ultra-DI DI400P and it does the job perfectly. https://www.amazon.co.uk/gp/product/B000KUA8G6/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1