New space, Amps all hum now?

sepiareverb

New member
Moved my recording area to a new part of the house, quieter in general, till I plug in my amps. Orange Rocker 15 and a Supro 1605R, both fairly new, both worked perfectly well before I carried them down to this room.

I have tried different outlets, a HumX, and moving them but there is still hum. The same hum in both amps, so would seem to be a power issue correct? New wiring, new breaker, professionally installed.

Any help would be appreciated.
 
Doubtful, but I will check. This electrician has done a LOT of work for me over the years (I'm a landlord by day) and is top drawer. He will absolutely check it without any offense taken, so will check.
 
Check that you have isolated ground 's' in you new room circuits. If you can, have him separate them.

I had that done in mine. Two breakers in main panel to basement studio. Each has a separate post in ground. I have never had issues with ground loops since.

Guessing you have a fight somewhere with lighting on the same feed.

But then, I am not a licensed electrician so...
 
I have a similar thing going on in my recording space. If you figure it out please post the fix. Thanks
 
... and a Supro 1605R,

Man, my old guitar player had the Supro 2x12. What a great sounding amp that was...

Hope you get your grounding issue fixed. I finally found my issue after like 8 years. I would only get it when I plugged the keyboard into my interface. Turns out the interface, PC, etc were all going through a UPS while the keyboard was plugged straight into an outlet. There is about 3volt difference and it caused a hum. Surprised it didn't cause any damage.
 
Will try and dive in this coming week, but there is a lot going on for work, so might be another before I can get him here.

I really can't believe the 1605R. Absolutely incredible. Reverb gets a bit deep right quick on the pot, but I'll learn that.
 
So many things can cause a ground hum. Cheap power strips, running power cords too close to microphone or signal leads, house wiring issues and other things on the same breaker, causing issues, like light fixtures or similar. New space, you could have missed one of these wire issues, if you haven't already looked for these.

If your electrician has all hot and neutral wires correct, have him check for other things on the same breaker. Moving your music room to its own breaker, if you have one, could be good. It's good that you have a professional doing this, as it's so easy to make mistakes, if you aren't one.

A separate ground, as was already suggested, is also a possible fix. But, if these amps were all doing OK in the previous room, it does seem strange, if the whole house is on the same ground. It sounds more like something else is on the same breaker. But, even if it doesn't fix this issue at hand, giving this room its own ground would be a good thing to do, if it's not going to cost you too much.

It is strange how electricity can cause such things, when it doesn't appear like anything is really different. Check things like wall warts, since many of them only have two prongs and no real polarity blades. If you can, unplug all of these, to see if the hum leaves. If it does, plug one it at a time, to see which one is the problem. Another thing to try is to flip those around, one at a time, to see if one of them is causing an issue. If you check one and the hum doesn't change, put it back how it was. Check each one, in turn, to see if one is maybe causing a hum. Of course, if one of these is powering the unit that is humming, it might be the first one you want to flip.

Always use good quality power strips. A $10-$15 6 outlet strip isn't good quality. It will work fine for powering lights, but in a studio, it can cause problems. Also strange, back several years ago, I had all of the bulbs in my studio incandescent. To save a bit of cash, because incandescent bulbs were difficult to find, I changed them to those pig tail bulbs. I was told they wouldn't cause a problem. They did. But, instead of having to replace every bulb with incandescent, I just had to change out one and the hum went away. Electricity is sometimes pretty strange. Now, they're all LED. No problems, there at all.

Hums are annoying, I know. I've changed out all of my power strips and thought everything was better than it was before, but I ended up with a hum. It looked great, but sounded like Sh*t. Talk about annoying. Sometimes, it's just a process of elimination by turning things off in a sequence, to see if something changes or removes the hum. Sometimes, it's a combination of two units that are causing the hum, each alone, not humming. Moving one to another power strip could be all it takes to fix that.

Good luck. You'll find it, and the satisfaction of silence will be near overwhelming for you. You'll have a smile on your face for days.
 
I not privvy to the machinations of the American electrical system except to say you seem to get a WHOLE lot more bother than us Limeys!

The thread talks of "ground loops"? Cannot be that if just one amp hums. I would be looking for a BIG mother transformer somewhere.

Dave.
 
I not privvy to the machinations of the American electrical system except to say you seem to get a WHOLE lot more bother than us Limeys!

The thread talks of "ground loops"? Cannot be that if just one amp hums. I would be looking for a BIG mother transformer somewhere.

Dave.

Not trying to give you guys any props, but you've had a few more years to get things right than we have, over here, in the states. But, I think he said both of his amps are humming. That could be just one amp causing the whole deal, though. And yes, it could be a transformer somewhere. I was wondering if this was a house, an apartment or a duplex setting. Something like that in your close neighbor's residence could be a problem. Maybe his neighbors downstairs are growing pot and they have a long line of massive powered grow lights?:facepalm::D
 
Not trying to give you guys any props, but you've had a few more years to get things right than we have, over here, in the states. But, I think he said both of his amps are humming. That could be just one amp causing the whole deal, though. And yes, it could be a transformer somewhere. I was wondering if this was a house, an apartment or a duplex setting. Something like that in your close neighbor's residence could be a problem. Maybe his neighbors downstairs are growing pot and they have a long line of massive powered grow lights?:facepalm::D

The history of power distribution is a complex and tortuous one. Italy was about the first to have AC distribution. USA had such a link around 1886. In UK the National Grid was not really established until 1933 but we did have one advantage, it would seem back then politicians were either rather technically smarter than todays (I mean, BLEACH FCS!) or they were at least cute enough to leave such heavy engineering to the engineers. Now, I have no idea of the 'color' of that administration but they did have the good sense to see that a National Grid HAD to be a NATIONAL effort. It is one of my eternal rages that WE the then taxpayer built the grid and Maggie bloody Thatcher all but gave it away to the fat cats.

But the UK power grid was not fully rationalized until many years later. I well recall going out on 'Voltage Changeovers' in the 1960s. Now we all get a 'nominal' 230V rms.

If, our lecktrik is 'superior' to yours it could be down to the fact that most folks are served from a Big Mother substation (we is talking minibus sized and housed in what even you would consider a palacial garage sized building) rarely more than a click or so away. Power comes in from under the road 'screened' in armour. At the entry point to each home, neutral is tied back to the armour but 3 wires are still run*, Thus 'earth' really is earth!

But YOUR hum problem friend! Fire up just one amp with nothing plugged in. Does it hum? If so, spin it around, does the hum change level? We need you see some simple, step by step tests if we are to nail this.

*I do know that there are various forms pf "PME" so, any power engineers our there, pleas don't shout at me! I am not one.

Dave.
 
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This is the same problem I have. I just moved into a new place and get amp hum. The weird thing is that it doesn’t happen all the time so I suspect that something else being on causes it.
 
This is the same problem I have. I just moved into a new place and get amp hum. The weird thing is that it doesn’t happen all the time so I suspect that something else being on causes it.

As with RF problems it is a very good idea to keep a log. Start time. stop time, day. For instance, if only happens mon thru fri, 8am to 5pm could be industrial. And it still could be RF. a big RF plastics welder would resolve as 100/120Hz hum.

Dave.
 
You might want to check for a situation known as a "split neutral". Each hot wire from the main box should have a neutral that goes with it and extends out to the load. When current flow out from the hot wire to the load, the same current flows back to the box through the neutral. Since the two wires are next to each other and the currents are equal, the magnetic fields somewhat cancel each other out and there is little magnetic field around the wire. But assume a situation with a ceiling light. The Neutral is connected to the light, but the hot wire goes to a switch on the other side of the room and that goes by a different path to the light. Now you have a large loop of wire with a current flowing through it that is generating a substantial, hum-generating magnetic field. The same thing can happen if the electrician joins several different neutrals together at a point and the current through a certain neutral doesn't match the current of the hot wire that is with it. Then you have an unbalanced situation and a magnetic field is generated in the room. This situation usually will cause hum in guitars with magnetic pickups, dynamic microphones, and microphones with transformers.

This does usually not cause electrical problems or safety hazards, but it will cause unwanted magnetic hum. Not sure if this is the problem in your installation, but it's worth checking.
 
So we ran a new ground today and still have the hum, which would appear to point towards some sort of interference coming from somewhere? My electrician really thought that this ground would be the fix. He is friends with a guy who has done live sound for the local college for 30+ years, they are going to chat some. Breakers are very dedicated. On the offending circuit there is the panel outlet (unused) at the other end of the house, and then a single pull chain light before it comes into the studio room, this light is rarely in use and doesn't effect the hum. I'm wondering about a new router we just got while I was in the process of moving into the new room, or perhaps the new water meter we have. I may invest in a lot of lead flashing hah!
 
Either of those two devices "could" be causing your issue. At least you can unplug the router to eliminate it. The water meter...I'm not sure how you can eliminate that. The new water and electric meters around here are know for causing minor interference if very close to certain devices.
 
Can you beg or borrow a 1kW UPS and run an amp on battery power with all the house juice off?

That will prove the house electrics good or bad.

That neutral thing sounds dodgy! Hard for it to happen here, at least in domestic premises. Both power and light is wired in 3 core side by side in an overall PVC sheath. Each light gets three cores from the switch in (I think 1.5mm area 3core) and power is a 'ring main' in 3core 2.5mm. Ring is usually fitted with 30A breakers but might be 16A. Individual equipment such as an immersion heater or cooker would be fed from a separate single 3core, 2.5 or 6mm.

All new breaker boxers, we call them "consumer units" have to have an overall RCD built in.

Dave.
 
Can you beg or borrow a 1kW UPS and run an amp on battery power with all the house juice off?

That will prove the house electrics good or bad.

That neutral thing sounds dodgy! Hard for it to happen here, at least in domestic premises. Both power and light is wired in 3 core side by side in an overall PVC sheath. Each light gets three cores from the switch in (I think 1.5mm area 3core) and power is a 'ring main' in 3core 2.5mm. Ring is usually fitted with 30A breakers but might be 16A. Individual equipment such as an immersion heater or cooker would be fed from a separate single 3core, 2.5 or 6mm.

All new breaker boxers, we call them "consumer units" have to have an overall RCD built in.

Dave.

That usually prevents this situation unless someone purposely uses a single wire to the light switch. In my case, being in the Greater Chicago area, my house is wired with conduit. Multiple neutrals and circuits were pulled through a single conduit and interconnected. When I remodeled my kitchen a couple of years ago the neutrals for one circuit were looped through outlets on another circuit. If I disconnected a neutral on an outlet with no power to it, something on another circuit would go off. It's a mess. I still have a split neutral issue on the lighting in my studio somewhere in the old wiring. The transformer in my AKG414 picks up the hum as well as dynamic mics and guitars. If I shut the right lights off I can record. Looks like a winter project.
 
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