Noise issues can be difficult to track down. Ground issues usually are a zzzzzzz type sound. First thing to try is running an extension cord to other plugs in the house. You want to make sure your not plugged into a circuit that has a fridge, or AC plugged into it as anything with a compressor will cause noise.

You can also test briefly with a 3 prong to 2 prong "ground lift" adapter. This will help identify if grounding is the issue. It's not a long term solution since your amp will be un-grounded.

If that works then the long term solution would be an isolation transformer, which is a box you'd plug into the wall, then plug your gear into. You could also fix the problem at the electrical service for the house.

Power conditioners generally don't reduce much noise.

The noise could be lots of things and could be a combination of things. Starting with the ground makes sense, then methodically moving on from there as needed.

kmetal wrote:
Noise issues can be difficult to track down. Ground issues usually are a zzzzzzz type sound. First thing to try is running an extension cord to other plugs in the house. You want to make sure your not plugged into a circuit that has a fridge, or AC plugged into it as anything with a compressor will cause noise.

You can also test briefly with a 3 prong to 2 prong "ground lift" adapter. This will help identify if grounding is the issue. It's not a long term solution since your amp will be un-grounded.

If that works then the long term solution would be an isolation transformer, which is a box you'd plug into the wall, then plug your gear into. You could also fix the problem at the electrical service for the house.

Power conditioners generally don't reduce much noise.

The noise could be lots of things and could be a combination of things. Starting with the ground makes sense, then methodically moving on from there as needed.

All good things to check. I would make sure you do not have any SCR light dimmers in your house as these can cause a lot of problems. I good way to check for "airborne" problems is to take an AM radio, tune it off any radio stations and walk around your house and see if you have any "noise generators"... You will hear a buzz when something is generating a noise. Best of luck!

Good tips there never thought about using a radio like that!

One other thing to try is that if you have a circuit that has nothing else on it including lights plug your whole system in the the one plug if 15 amps will cover your needs.  When you start mixing and matching circuits you are bound to find problems.  You can also plug in your guitar first and then plug on unit in at a time to see what is causing the issue. 

Are you in North America? Are you able to confirm your power outlets are wired to code?  Ie the hot wire actually go to the hot connection on the outlet?  It is not uncommon to find the neutral and hot reversed in residential  wiring. This can cause all sorts of noise issues.