Axe-Fx III is making my other stuff buzz!

I traced the problem to the IEC cable. It is all good now. Thanks for all your suggestions.
I have similar issue, as soon as I plug the IEC into my axefx I get a buzz. I tried coppper grounding it, different plugs in the house, and different IEC cables even high grade ones for PAs and it still buzzes. My kemper, quad cortex, dead silent
 
I traced the problem to the IEC cable. It is all good now. Thanks for all your suggestions.

Do you know what the specific defect in the IEC cable was, or was it more like “swapped IEC cable out, problem gone and we’re done”? I’d be interested to know for future reference.
 
I have similar issue, as soon as I plug the IEC into my axefx I get a buzz. I tried coppper grounding it, different plugs in the house, and different IEC cables even high grade ones for PAs and it still buzzes. My kemper, quad cortex, dead silent
You have a ground loop. You need to break the ground loop. A Humbuster cable will break the ground loop. It is preferable, however, to use the XLR outputs. Those outputs have ground lift switches.

Those Kemper has ground lift switches (which can be dangerous) and the QC is not grounded since it uses a wall-wart. That's why you're not getting buzzing with them.
 
Thanks I fixed it using a cheater plug ground lifter for 89cents at home depot. Dead silence instantly.
NO. DON‘T. Please …….

Never, never, never lift, cut oder insulate your POWER ground.
You are in extremely high danger of electric shock.

You may lift audio ground but NEVER power ground.
 
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Regardless of how you cable up I would put a washer in the front and back of each rack tang and make sure all power comes from a single source (single path to ground).

An excellent suggestion — as long as said washers are NON-CONDUCTIVE and prevent the rack screws from touching the equipment rack ears. In our studio racks we actually replace the metal rack rails with wooden rails (typically 3/4”x1-1/2” soft white pine, painted black) and leave 1/2” space between adjacent pieces of equipment mounted using wood screws and #8 plastic cup washers (so that no chassis touches anything metallic). This ensures that the grounding point of each unit is singular and isolated from any other ground.
 
Regardless of how you cable up I would put a washer in the front and back of each rack tang and make sure all power comes from a single source (single path to ground).



Humfrees.

20211127_185722.jpg
 
…. make sure all power comes from a single source (single path to ground).
This ! ^^^

In other words: avoid using several different wall plugs. Use one wall plug.

Having exactly just one main power line and thus precisely one path to ground is by far the best working point in setting up a troublefree - including humfree - audio environment.

This cannot be overestimated and should always be your starting point.
 
This ! ^^^

In other words: avoid using several different wall plugs. Use one wall plug.

Having exactly just one main power line and thus precisely one path to ground is by far the best working point in setting up a troublefree - including humfree - audio environment.

This cannot be overestimated and should always be your starting point.
This isn't always possible though. If you are running a long cable to a mixing board, for example, it's virtually impossible to ensure the same ground potential at both ends of the cable. Balanced (i.e. XLR) cables are ALWAYS the best choice for these scenarios. 1/4" cables should only be used for short runs between equipment. If you must use 1/4" cables when connecting equipment plugged into different outlets then Humbuster cables should be used.
 
This isn't always possible though. If you are running a long cable to a mixing board, for example, it's virtually impossible to ensure the same ground potential at both ends of the cable. Balanced (i.e. XLR) cables are ALWAYS the best choice for these scenarios. 1/4" cables should only be used for short runs between equipment. If you must use 1/4" cables when connecting equipment plugged into different outlets then Humbuster cables should be used.
As I said …. a good starting point to avoid hum loops.

Certainly there are a other remedies to avoid or cure the problem, too.

Balanced audio lines are always the best choice for analog audio lines. And I am quite certain everyone agrees.

But hum loops are some times tricky nasty and can introduce in several ways. No problem to solve if you have time to. But if time matters I prefer to be on the safe side.

And indeed for decades now I always have the FoH mixing desk running on the same ground potential as the audio stage equipment running in front of the FoH mixer.
For locations with audiences up to, say a few hundred, it‘s very easy to do. Simply add just one power line to the already existing network audio line (in earlier decades: the multicore) between stage and FoH. That’s is - and gives you a lot of additional certainty to avoid hum problems.

You might correctly argue that the resistance of the long power line influences the ground potential in a similar way a long inhouse power lines does.
On the other hand I‘m in no way aware of the status (phase, grounding) of the wall plugs I find in a certain location. The status of my power line between stage and FoH mixer I know and can trust in.
 
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I have some outlets in the house that are only 2 prong. Those little 3 to 2 adapters aren't safe? Why do they sell them? I ask because I don't know.
 
This isn't always possible though. If you are running a long cable to a mixing board, for example, it's virtually impossible to ensure the same ground potential at both ends of the cable. Balanced (i.e. XLR) cables are ALWAYS the best choice for these scenarios. 1/4" cables should only be used for short runs between equipment. If you must use 1/4" cables when connecting equipment plugged into different outlets then Humbuster cables should be used.
what is the correct way for presenting the Humbusters to a rear of rack patch panel. Should it be wired pin S to S, R to R and T to T?
 
I have some outlets in the house that are only 2 prong. Those little 3 to 2 adapters aren't safe? Why do they sell them? I ask because I don't know.
They are safe when used properly. If your 2 prong outlets have metal boxes and conduit and the conduit is earthed then you remove the screw from the wall plate, plug the adapter in and replace the screw. Ground is provided via the screw.

They're unsafe when people use them to lift the ground. The chassis of the connected device is then not earthed. If a fault occurs whereby the line voltage is shunted to the chassis the chassis is then live which presents a shock hazard.
 
They are safe when used properly. If your 2 prong outlets have metal boxes and conduit and the conduit is earthed then you remove the screw from the wall plate, plug the adapter in and replace the screw. Ground is provided via the screw.

They're unsafe when people use them to lift the ground. The chassis of the connected device is then not earthed. If a fault occurs whereby the line voltage is shunted to the chassis the chassis is then live which presents a shock hazard.
This. Totally this.

Lifting the ground on a power connection can and does kill people. And many people do it because “I’ve done it lots of times, and I’m still alive,” or “I don’t know anyone who died that way.”
 
This. Totally this.

Lifting the ground on a power connection can and does kill people. And many people do it because “I’ve done it lots of times, and I’m still alive,” or “I don’t know anyone who died that way.”
can you die from typical American household voltage? I can't count the number of times I've been zapped. My wife would say that explains a lot.
 
can you die from typical American household voltage? I can't count the number of times I've been zapped. My wife would say that explains a lot.

First crew job on a major tour in England. Boss says “here, hold this” and hands me the end of a guitar cable. I’m standing on stage listening to a buzzing Fender Twin and waiting, when he suddenly yells “CATCH” and tosses me a cabled SM58. I feel the POP of 240V across my palm, and as everyone else laughs hysterically Boss bellows “and THAT’S why we ALWAYS check EVERY ground on EVERY piece of gear on my stage, Mate”. Since I wasn’t dead, he then showed me where another Twin was stashed in the lorry (to replace the one he and I apparently just killed) and taught me how to properly check AC grounds with a neon test lamp.

I still have a thin 1/4” scar line on my right palm.
 
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