Discussion in 'Recording/Live Sound' started by maydaynyc, May 26, 2019.
Seriously, get a Furman power conditioner and try it. If that’s not the problem send it back.
Bad situation with the venue’s lighting!
The LED bar is probably not the problem but par cans IF on dimmers and fluorescent lights are almost surely the main problem. Good luck dealing with those with line conditioners as the noise is airborn. One suggestion is to make sure the par can lights (if on dimmers) are full on, or off. Typically dimmers make the most noise when dimmed way down low. Still you might see if you also can get the venue to temporarily unplug these lights sometime as a test.
This is exactly correct.
The ability to null the noise level with position relative to the hum field is the classic signature of 60 cycle hum. It's the pickups, exacerbated by other things in your chain.
Most "humbuckers" aren't really 100% humbucking.
I am very much inclined to be of the same opinion. You're on long Island, and mostly play in Manhattan, I would imagine. Those venues are all old as heck, and I'm sure their wiring is very antiquated. Heck, a lot of them should be condemned they're in such bad shape. Power conditioner sounds like what you need most.
I would test the rig with another guitar. A known well shielded guitar. No noise with the guitar turned down would indicate it as the source of the noise (or at least some of the noise). A semi-acoustic is more prone to RF noise as there is no interior or pick guard to shield to effectively make a sudo Faraday cage.
BTW, I would assume that the live environment has much more RF noise than your rehearsal space and that's why the problem manifests itself in only one location...
If the buzz is only there in certain orientations to the Kemper...maybe turn the Kemper
We played one night in a building from the early 20s I had plugged an amp into an open outlet, plugged in a strat, and proceeded to listen to a bunch of different radio stations all on top of each other along with all sorts of other sounds. Humbucker guitar was better but still not great. Ran an extension cord from the Furman conditioner in the gear rack and silence ensued. Just try a line conditioner, you can get one for 100 bucks or less on Amazon. Make sure it has a free Returns. If it doesn’t fix the problem send it back. A hell of a lot easier than ripping guitars apart looking for bad wiring, buying special cables and what not.
Also, if the venues are old there is a chance the outlets aren’t grounded. I lived in a rental that was that way. Amps and guitars made interesting sounds and if you didn’t wear rubber soled shoes you also found some other fun if you touched anything metal.
is there is there anything I can do equipment wise to address it?
One of the biggest causes of buzz is NEON SIGNS - especially close to the stage. If you happen to see one, casually turn it off for second to see if it makes a difference.
Light dimmers, and flourescent lights are also common causes.
A noise gate also helps a lot, especially if it is set just to close when you are not playing at all.
I do have a noise gate on my kemper and I was using it, but unless you're playing Green Day or Ramones where the guitar is going Non-Stop, many Tunes have lots of space where it's not quite enough time for The Noise Gate to work without having to set it too stuttery.
I played with the same equipment somewhere else yesterday and it worked fine so I'm fairly confident it was Airborne noise at the venue. I may try picking up a power conditioner, but I highly doubt it will make a difference and I hate having one more thing to carry.
Are you carrying a power strip right now? If so might as well carry one that is a line conditioner as well. I don’t EVER recall having problems with airborne noise, but lots of instances of dirty power. I don’t understand your reluctance on this. You dropped 2k on a keeper amp but 80 bucks is a problem? Hell with amazon prime you would have known in 2 days if that was the problem instead of mind screwing this for how long?
It's not the money, I'd spend a whole bunch if I knew I could fix the problem, in fact I just dropped some coin on some top shelf mogami instrument cables to see if that might help as well. Its that when I think of power conditioner I'm thinking of a big, heavy piece of rack equipment, not a fancy power strip. I'm skeptical the power strips actually do anything other than provide some mild voltage fluctuation protection. But you make a good point, might as well try everything. I'll look into a power conditioner.
I have an outdoor gig afternoon but I'm going to play a combo amp and some pedals so different rig under very different conditions.
Rack mounted but not heavy
Why so much mystery & bad info here?
AC power isn't voodoo. There's like, 2 or 3 guys here who seem to actually seem to know what they're talking about.
First... those $100 Furman strips aren't power conditioners. They'll do nothing for dirty power. I own a bunch & use 'em but really they're just overgrown power strips that make things convenient. What the real function is, over a $20 power strip is that they'll self sacrifice in extreme conditions. Blow themselves up before the voltage can get to anything downstream...
That includes high/low voltage from the wall and also something downstream backfeeding power and blowing everything else up. The Furmans will take it and die. I killed one of those $100 boxes at a festival a couple years ago. Ran all day Friday for setup, all morning Saturday until the second band came on and "pooof" - lost power to the whole stage. PA, backline etc in the dark. Chuck it and buy a new one.
A real power conditioner that can handle dirty power is going to have an isolation transformer, weigh at least 15-20 pounds and start around $1k. If your in the Furman family that'd be something like a P1800 or 2400 AR. Not $100 but more like $1500+ Also look at Equitech... the kings. About $3k.
If the PA was humming before you got there it's a sure sign of dirty power and everything goes downhill from there like a skier who bailed out of the gate & just keeps tumbling.
PA humming madly IS indeed the sign of dirty/non existent ground.
What he's saying is to go to the hardware store... Home Depot or whatever and spend $10 on outlet tester.
Pretty clutch device that tells you if the outlets are wired correctly before plugging anything expensive into them. Can save a lot of hassle, and possibly even lives in extreme cases. Essential gear.
I have several scattered around... maybe even a dozen? In gig bags for both guitar & PA rigs... one in a tool box in my truck, couple more in my main roller chest...
Don't automatically assume that the wiring is new & good or old & crappy. Need to verify before plugging in. Year or so ago some friends asked if I could drag out my little Fisher Price PA for a backyard party they were playing. Said the part of the yard we're in is all new... all new wiring, just built. Well, outlet tester showed the "new wiring" had an open ground.
Guess what?! We ain't plugging ANYTHING in.
Next nearest outlet, wired properly was at the house... nearly 100 feet away. Good thing I carry 10 & 12 gauge cords and even then, running the whole shebang off a single 15amp source was pretty dicey.
Not disputing your expertise. But every time I’ve had what the OP describes those 100 Furman took care of the problem. So clearly there is more there than just a power strip. My entire point is you can find out for FREE. If it doesn’t solve problem send it back.
My experience is that the noise has to be pretty bad for it to bother anyone on stops in songs (if they are too short for the noise gate to kick in). I think that kind if like persistence in vision (the stuff that makes movies look seamless instead of 30 pics per second) that we also have some persistence in hearing in that our ears are attuned to the louder volume levels and won't really notice short term noise on a short break. A noise gate that shuts off after 1 beat (500 ms or so) should do the trick without triggering too much. I use a gate built in to my OD pedal and never notice it at all.
Jmoose to the rescue again, thanks that confirms both what I believe about the cheap "power conditioners" and clears up the outlet tester. No brainer to buy a couple. I will add that in my case I did use a Ebtech hum-x that did not solve the problem. that, plus being able to reduce the noise by rotating my guitar, led me to decide it was airborne. Any thoughts on how to deal with with that besides shutting off the offending lights? I ordered some high end shielded cables to see if it helps, but anything else I can do within reason?
Like I said not going to dispute Jmoose experience. However you could read reviews from all sorts of owners who describe them solving what your talking about.
And the fact you can literally try for free what do you have to lose? Your trying all sorts of other things so why not? No I don’t work for Furman, just throwing out personal experience.
Ok, one thing I didn't see come up here is the subject of ground loops and the differences between audio ground, Pin 1 of an XLR and the shield on a guitar cable vs AC power ground and how they're actually tied together. That's where the rub is.
Post #4 You said the PA was humming without you connected via XLR/DI from Kemper to PA yes? Was buzzing loudly even with clean patches?
That's the sign of something mis wired at the AC panel or outlet. Could be other things but that's the most likely cause and the only fix is calling a licensed electrician who knows the difference between their asshole and a screwdriver and having it fixed properly. Chances are good there was stray voltage hitting the ground & neutral which is where the buzz is coming from.
Once ground of any sort is contaminated, has voltage on it everything is going to buzz. 60 cycle hum, 120Hz line noise - aka "mains hum" infects every other piece of gear connected to the rig.
Cheap Furman boxes do have some filtering but won't solve truly dirty power and just pass it on. The noises they'll take out are line switching, like if you insist on having a fridge connected to the same circuit as the audio gear and get clicks & pops when it turns on/off?? CheapO Furman might take care of that.
Lets assume the PA has dirty power at the mixing console, ground from that wall is dirty...
The dirty AC ground on the console is tied to the audio ground of that console, and that dirty power is going to contaminate every Pin 1 contact on the desk. Both inputs and outputs. So when you plug the Kemper DI into the desk that audio ground is now directly connected to the guitar in your hands! Same goes for the main & monitor cabinets!
In theory hitting ground lifts should isolate the Kemper from that bad ground at the console, in practice I've found that not all ground lifts are equal. Another rub is that if the power is really dirty throughout the building there's probably bad power at the Kemper amp itself and so, throwing the ground lift won't make a large difference. Won't go from buzz to no buzz, but more like lots of buzz to slightly less/different buzz.
The Hum-X not working is a sign of that... severe ground loops. Possibly from different circuits and even phase between circuits which can be a nightmare to figure out.
One item you can/should carry are XLR barrel ground lifts. Can stick these between the XLR send and the console to see if it isolates and cleans up noise. Another piece of essential gear.
Between the Kemper, personal monitor wedge and the console there are a lot of interconnected grounds both audio and AC. Ideally everything is on the same AC circuit and has the same path to ground. Often, not always the case and so the troubleshooting has to start.
Honestly this is one place where traditional amps have an advantage... Hang a mic on a Fender and your grounds, both AC and audio are always going to be completely disconnected from whatever's happening at the console.
And its not just the console! Could be anything in the PA rig, even the mains cabinets. If they have dirty power on some other leg of the AC, guess what?! Audio ground cycles it back to the console, which cycles it back your fancy potato DI amp rig.
This is all usually 110% solvable if there's enough time to start troubleshooting, and hopefully the room is quiet enough to troubleshoot... If you don't have the time & the room isn't quiet enough 'ya usually gotta grin & bear it for that show. And if there's a particular room or set of rooms that have bad power, you always have the option to complain and have 'em fix it or never play there again.
Jmoose, thank you for your time and knowledge!