Ground hum when using AX8

BobBrault

Inspired
Ok, I have this issue of ground hum with my AX8. It only happens at this one venue where I regularly perform. Every other venue that I play at, I have no problems. Now, I have run into ground loop situations before and I think I know most of the troubleshooting steps. However, this one has me stumped. I've tried adding a ground isolator to my signal chain and hum is still there. Tried different electrical circuits, ground lifts, turning off stage lights. All to no avail. I am running stereo out with XLR cables direct to mixer and using IEMs. To get through the gig, I have to push the noise gate pretty hard which kills my sustain/tone. Again, all other venues the AX8 output is quiet. So, if anyone has some other ideas/solutions, I would greatly appreciate your input.

TIA,
Bob
 
Do you know if the guitar needs to be plugged in and turned up to get the noise, or is the noise there with nothing plugged in?
 
I assume you checked the ground. Some venues have lousy if no ground at all in some of the outlets. Even it it looks like they are wired.
 
I assume you checked the ground. Some venues have lousy if no ground at all in some of the outlets. Even it it looks like they are wired.
Thanks for the response. Yes, ground was checked. It's a high end casino venue. They have dedicated circuits for the stage. I ran a circuit tester and it shows ground and polarity are correct. Also, I tried connecting on the same circuit as our mixer. Then I tried the AX8 on it's own circuit. Still same result. All our other gear, dead quiet. I'm going to solve it eventually as we perform there often. I'm just tossing this out there in case someone had a similar experience and maybe an idea to try.
 
Do you know if the guitar needs to be plugged in and turned up to get the noise, or is the noise there with nothing plugged in?
Thanks for responding. Guitar plugged in, noise. When I mute to tune, no noise. Quieter with humbuckers but still apparent. Single coil guitar, the hum can be obnoxious. Guitars have shielding and grounding of shielding/bridges were good.
 
Some venues (and studios) are just prone to be noisy with guitars. I always have my volume pedal down when I am not playing and have always done this to get around it.
 
Some venues (and studios) are just prone to be noisy with guitars. I always have my volume pedal down when I am not playing and have always done this to get around it.
I understand that there are ways to get around it. I'd like to pinpoint the cause and work on a fix. It's one of those things that'll drive me nuts until I track it down. I've found some other threads on this. I should have done a search first, as there is already some good info on this posted.
 
I once had an issue with a bad channel, not sure if it was the line to the mixer, or the channel itself in the mixer.
If the hum only happens with the guitar plugged in it could just be picking up ambient EMF. Maybe, some highvoltage power lines running over the building?
 
Single coil Strats are a pain with neon lights. The Jeff Beck Strat had noise cancelling pickups that saved many gigs for me playing under a 'beer neon sign'.
 
I could be the lighting in the club. Does this happen with all of your presets?
Yes, it does happen with all presets. Clean or high gain. So, to be clear, it's not the AX8. Because of the nature of the venue ( casino bar open to gambling floor ), I can't spend time making noise and tracking it down. I know it's some external electrical field coming from somewhere. I did have the venue turn off stage lights, still same problem. Maybe I should bring a giant Faraday cage and stand in it, that might work...LOL. Anyways, thanks for any ideas.
 
Single coil Strats are a pain with neon lights. The Jeff Beck Strat had noise cancelling pickups that saved many gigs for me playing under a 'beer neon sign'.
I have tried a Strat with noiseless pickups. The hum is reduced but still there. I usually bring 4 guitars to gigs. Strat, Tele, Les Paul and a PRS 513. All hum to varying degrees. I don't think it's my gear. It has to be something external in the venue. I return there for 4 nights next month, maybe I'll figure it out by then. I was just putting it out here to see if someone had a similar issue/solution. Thanks to all who took the time.
 
I once had an issue with a bad channel, not sure if it was the line to the mixer, or the channel itself in the mixer.
If the hum only happens with the guitar plugged in it could just be picking up ambient EMF. Maybe, some highvoltage power lines running over the building?
I don't think it's the mixer. However, the high voltage/EMF is my thought, also. The venue's sound tech says he's never had an issue with other acts.
 
Since there's no hum with the tuner on/signal muted: that implies the hum is before the XLR outs: Probably EMF picked up by either the guitar or the input cable. I have encountered venues where a bad hum starts and stops seemingly at random: presumably when something somewhere turned on and off: power lines? communications relay? surveillance team moved on? bees moved the hive? No control over that. A guitar cable that works fine everywhere else may not hold up to Chernobyl like levels. If you haven't already: try a cable that has both braided and foil shielding, or a braided plus conductive PVC shielding. I guess there's always Tin Man or Ironman cosplay (as a quasi-Faraday cage) if all else fails.
 
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Just out of curiosity, try putting electrical tape on the power cord from the axe-fx to the power outlet and see if the hum disappears, this helped with my axe-fx ultra. This is not safe, so don't do a gig like that, but it might help you pinpoint the source of the problem.
 
That's not a ground loop. That's your guitar picking up EMI from something. Some venues are like this. There was one place we used to play regularly and I couldn't use a single coil guitar there. There was a large transformer behind the stage and neon lights near it. Even with humbuckers the noise was prominent. There was one spot that if I stood just the right way and didn't move the hum wasn't too bad. Move at all and bzzzzzzz.
 
I have tried a Strat with noiseless pickups. The hum is reduced but still there. I usually bring 4 guitars to gigs. Strat, Tele, Les Paul and a PRS 513. All hum to varying degrees. I don't think it's my gear. It has to be something external in the venue. I return there for 4 nights next month, maybe I'll figure it out by then. I was just putting it out here to see if someone had a similar issue/solution. Thanks to all who took the time.

This is why I suspect EMI issues that your guitars pick up. Not much to do about it, maybe move to another position on the stage. Surprised humbuckers also has issues, they usually are good at cancelling EMI.
 
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ground loop or junk getting in through the guitar pickups?

1. Does it go away when you turn down the ax8 output?
2. Does it go away when you turn down the guitar volume?

I had a church gig for years that basically forced me to go to noiseless pickups on all my single coils. something in the dimmers just really wreaked havoc with singles. as a result I'm a proud zexcoil lover in my strat and kinman lover in my tele :-D
 
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