A weird buzzing problem...

thecolourbox

So this is strange. I have some quiet time at home tonight so I thought I'd try out my in progress small pedal board tonight. Discovered a very odd buzzing issue, most noticeable when I have the Big Muff but it's still there when I disconnect that completely.

Basically I had a Whammy plugged into a different plug socket, not connected in any way to the other mini board, when I touch the switch on the Whammy it increases the buzz on the other signal path!

Video evidence:


Really weird, does it with any of the pedals upon further inspection albeit quieter (obviously given the gain on the muff).

Do I need to get my house completely rewired?! Why on earth would it do this??

Excuse any mess you can see in the background on the video as it's a work in progress...

skunkwerx

I reckon one of those somethings that is plugged in has a plastic ground pin at the mains. 

Are those speakers plugged in and on too? 

I have a similar issue. 

All my guitar gear is plugged into a mains outlet one side of the room. The amp in one socket and the pedal board psu in the other. 

If I plug my speakers in over the other side of the room, instant buzz comes thru the amp.. the only path is thru the mains for it to do that. 

I only noticed this because I plugged my iphone in to charge while playing once, and as most iphones with the metal backs do, they vibrate slightly when running a finger over the back when its plugged in and charging. 

This vibration shit also happened on a pair of bookshelf speakers I used once. Their metal control plate/chassis had the same vibrationy weirdness. Apparently its a voltage not strong enough to do harm and is fairly common. Seems like its a ground thing. 

However. It seemed to travel thru the mains and make the amp buzz, but also then make all the metal parts on the guitar vibrate too. Which I did have beef with, 1. Because gear is fucking expensive and that cannot be doing the lifespan of it all (pedal chain, amp, pickups) any good, and 2. Because when I touched the strings with my arm whilst touching whatever other device I had plugged in over the other side of the room, i got a burn/shock sensation. 

Not major but surely people play guitar thru an amp with speakers plugged in somewhere and don't seem to get this? 

I didnt like the idea of that ground thing going thru my guitar giving it a pissing vibration sensation. 

If you plug in your amp and board as usual and plug a cable into the amp and turn the amp on but don't connect a guitar to the other end of the cable, turn the amp gain up and volume a bit and as normal you'll hear the usual buzz of having a cable plugged in with no guitar at its end. 

Then turn the mains on for the whammy wherever thats plugged in, I bet you hear the amp buzz louder when you do. You could probably replace the whammy with xx amount of other things and get the same result. 

thecolourbox

There's no amp on, it's through the purple monitors on the window ledge. It's very odd. Not aware of any plastic plug sockets but not quite sure what the ground pin is either.

Plugged in on the window plug is the big extension lead, with the Digitech modeller, the Trex fuel tank, two monitor speakers, the mixer, and a sound bar thing which I can remove and still have the same issue

skunkwerx

thecolourbox said:

There's no amp on, it's through the purple monitors on the window ledge. It's very odd. Not aware of any plastic plug sockets but not quite sure what the ground pin is either.

Plugged in on the window plug is the big extension lead, with the Digitech modeller, the Trex fuel tank, two monitor speakers, the mixer, and a sound bar thing which I can remove and still have the same issue

You know that mains plug to the left of your whammy, the top pin on that is the earth. I reckon either your speakers or whammy have the same plastic pin

thecolourbox

skunkwerx said:

thecolourbox said:

There's no amp on, it's through the purple monitors on the window ledge. It's very odd. Not aware of any plastic plug sockets but not quite sure what the ground pin is either.

Plugged in on the window plug is the big extension lead, with the Digitech modeller, the Trex fuel tank, two monitor speakers, the mixer, and a sound bar thing which I can remove and still have the same issue

You know that mains plug to the left of your whammy, the top pin on that is the earth. I reckon either your speakers or whammy have the same plastic pin

"Runs off to have a look"

skunkwerx

Not that I know what it means or how to cure it mind.. I just found that devices without a metal earth pin seem to inject their noises into the mains and then out any speakers that are also plugged in somewhere lol!

But maybe if we can suss it out somehow we could find answers.. neo.. 

ICBM

If there's no proper amp then nothing may be earthed at all - a lot of modern kit like powered monitors isn't, and power supplies for pedals are usually intentionally designed not be since otherwise they cause an earth loop when the pedals are plugged into an amp. (The power supply casing/chassis will be earthed if it's plugged directly into the mains via an IEC cable, but the signal path ground should not be.)

thecolourbox

Right only one plug had the plastic ground pin, and that belonged to the sound bar I play music through. But makes no difference whether that's plugged in or not, same problem. Also the ironic thing is, the plug you referred to next to the Whammy is for a cheap old wireless system which actually does often cute my noise problems (not tried it for this one as I don't have any 9v batteries at present)

thecolourbox

ICBM said:

If there's no proper amp then nothing may be earthed at all - a lot of modern kit like powered monitors isn't, and power supplies for pedals are usually intentionally designed not be since otherwise they cause an earth loop when the pedals are plugged into an amp. (The power supply casing/chassis will be earthed if it's plugged directly into the mains via an IEC cable, but the signal path ground should not be.)

Ah ok, so I might need to sack off the monitors?

ICBM

thecolourbox said:

Ah ok, so I might need to sack off the monitors?

Or create an earth connection. If you have a pedal with a second output (eg the 'bypass' out on a Boss tuner), you can connect that to an amp which is plugged into the wall but not switched on if you don't want it to be.

thecolourbox

ICBM said:

thecolourbox said:

Ah ok, so I might need to sack off the monitors?

Or create an earth connection. If you have a pedal with a second output (eg the 'bypass' out on a Boss tuner), you can connect that to an amp which is plugged into the wall but not switched on if you don't want it to be.

Ah I have a boss oc3 which is otherwise useless so could try that but the only amp I have is a crap Fender Deluxe 112 thing with a dicey power cable so that would probably cause more problems than it would solve.

Electric guitar is way more work than it's worth

ICBM

thecolourbox said:

Ah I have a boss oc3 which is otherwise useless so could try that but the only amp I have is a crap Fender Deluxe 112 thing with a dicey power cable so that would probably cause more problems than it would solve.

As long as the earth wire in the cable is OK then it will serve as an earthing point - the amp doesn't need to be on, or even work.

Worth a try anyway.

thecolourbox

It's rather weird it's never come up before though. I'll try it, thanks

thecolourbox

Ah no that didn't work either!

ICBM

Hmmm... not sure then. Does the Fender amp work at all? If so, try that with the same pedals.

thecolourbox

ICBM said:

Hmmm... not sure then. Does the Fender amp work at all? If so, try that with the same pedals.

There's no working speaker so only through the effects loop send can I get a sound. I've no chance to test that now sadly probably for another week or so unfortunately!

thecolourbox

I did have a further idea that sadly proved to be fruitless - I thought I may have knocked the "ground lift" switch on the back of the GSP1101 whilst moving stuff about, which may have fitted in with the "no ground in the chain" idea perhaps. However I tried it both in and out (couldn't remember which way was which) and it seemed to make no difference whatsoever either way. Which I'll admit was a bit disappointing after I'd had what I thought was a clever thought!

prlgmnr

Noise is a pain in the fucking arse, I got a new PC for out in the studio the other day, the USB mouse I was using made a noise that came through my monitors even if the interface they're plugged into wasn't turned on, when I use a guitar amp and loadbox I get a load of whiney clickey crap which I think is from the PC power supply but could also be due to having the amp plugged in a different socket to the computer and interface, I need to fart around with ground lifts in the signal chain and see what does what.

I went with a fanless PC this time round and in the oasis of calm and quiet this has created I can hear that one of my monitors has a subtle hum that never goes away, even with nothing plugged in.

In the course of faffing about with all this I've noticed that my Mark V and JCM 800 have both developed a hum when run the normal way into a cab with the masters high that I'm sure wasn't there before (still there even with nothing plugged in, gets worse with all knobs all the way up), when the JCM did it I thought it might be due for the caps replacing but can't see why both amps would suddenly need that doing at the same time. 

Considering getting an electrician to install an independent ground for the studio so as to be absolutely sure nothing else in the house/buildings is interfering (I'm giving a particularly suspicious glance at the fan/pump etc in the boiler room).

Also worth taking a deep breath and reminding myself it's probably all fine for a home studio.

thecolourbox

I've had quite severe problems with various noises in the past in two days houses a numerous guitars and signal chains but this one seems a different noise and perhaps a different problem to previous ones.

I've not tried my current guitar through a computer yet but previous guitars have had the usual bizarre computer interference noise also. The other issue is Pod Farm only seems to work with the Line 6 interface but that interface is terrible and latency is too much, so it's a while other rigmarole to have two interfaces plugged in and a Daw project open just to host it with a different input etc etc that I just want to throw everything out of the window

thecolourbox

So I get no noise straight into the gsp.

I have unplugged everything off the extension by the window except the gsp (ie monitors not plugged in). With pedals plugged in by the door, connected to the gsp....noise. 

I've also tried a TC Teleport thing with a ground lift switch. Both positions = noise.

I tried disconnecting the gsp and using the pedals straight into the mixer. Noise. 

Bizarrely at one point the noise changed as I lifted the black square box thing half way along the power supply cable to the mixer so I've moved all that away from everything. Still noise.

What the hell is going on??? 

Two of the pedals are new but one isn't. Other old pedals make no difference.

ICBM

Gremlins.