What have you done to Eliminate Group Loop issues - noise/static/hiss ?

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Super Hans

      Hey all, I've read reading up on how to Eliminate Group Loop issues, noise, and static. When I run Laptop to DAC to AMP I get static/hiss sounds, esp when I move the Mouse. When I unplug the power to cable for Laptop and it's just running on battery All 100% of the static/hiss noise Goes Away. I have plugged Laptop, DAC, and Amp all into same Non-Grounded outlet and still have the problem when Laptop is plugged in. --
1.-- Does it matter if the Outlet you are plugging everything into is Grounded or not Regarding Ground Loop issues ? -- Even if all equipment is powered from same outlet will a Non-Grounded out give you Ground Loop issues ? -- 2. What have you done to Eliminate static/noise/hiss problems ?

I'm thinking My 2 Options that are pretty much guaranteed to Eliminate the Issues iare: 1--> a UPS that has an the inverter in in, not just a battery, I've read isolation transformers and online (pure sinewave) UPS will not cause noise/hiss problems unlike most regular USPs. OR 2--> an isolation transformer (which hum a bit, so have to put it not in listening room I guess). They aren't cheap and I've love to find a cheaper way to fix this but haven't found any on the inet. I'd prefer a USP since it also provide battery back for power outage. But I'd like to know you all's input on the Pros and Cons of Each (iso trans vs UPS)
I have a 3 hours charge on my Laptop so I just unplug the power cable and I have a few hours to listen to music with no noise issues. But I want to fix it so it's done properly.

DaveC113

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    I have plugged Laptop, DAC, and Amp all into same Non-Grounded outlet...


Non-grounded outlet?  :scratch:

You should try properly connecting your gear first, maybe... ground is not just for safety. I'm not even sure where to start here, but try plugging your entire system into a single grounded outlet.

Your issue with static/hiss coming from your computer is an issue with your computer and not a ground loop issue. A laptop is not a good solution for a music server anyways.

Super Hans

Thanks for the reply, forgot to mention the only grounded outlets are just in bathrooms and such. Not a grounded outlet near my listening room naturally.
Probably dumb question, but If I run a grounded extension cord to my equipment, will that resolve some of, if not all the issues I'm having ?

Speedskater

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It's not the ground, it's the loop area that may be the problem. But ground loops are about low frequency hum & buzz, not  hiss, noise & static.
Getting all the involved 3 wire chassis's connected together with short heavy wires is a good first step.
The 2 main problems are:
1] Internet, cable TV and remote PC's that are grounded elsewhere.
2] Poorly designed audio input connectors.
* * * * * * * * * * * *
While hiss, noise & static may be poor shielding or other interference problems.

Speedskater

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Only a 2 wire outlet. Is this a US type power system? If so an extension cord would be a quick check.

Super Hans

Thank You, for music I'm just using a laptop (foobar), to DAC, to integrated amp with passive speakers.
No TV cable or anything else. It sounds perfect until I unplug the laptop plug in the Laptop power cable

Super Hans

Thank You, for music I'm just using a laptop (foobar), to DAC, to integrated amp with passive speakers.
No TV cable or anything else. It sounds perfect until I unplug the laptop plug in the Laptop power cable

That's I'm hoping, a ground ext. cord from a grounded outlet, to a proper surge protector would work. As long as everything is plugged into same surge strip

Speedskater

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AH yes, laptops can be a hum, buzz & noise source.

rotarius

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Hiss, static noises are likely originating from the laptop, can you connect your system to another computer to see if it is the same result? 

Folsom

Laptop PSU's tie the SMPS ground  to safety ground (earth). It is a loop. The problem is its a filthy loop.

I would make a box with in and out plugs, and use a Schurter DENO on the ground. You could use a metal outlet box, 2ft 12ga cord, two marinco ends. Connect safety ground to the box and DENO at thr same point, and then connect the DENO to the output safety ground. You don't even have to strip the hot/neutral inside the box at all, just do an open-ground surgery.

That is how I'd do it, but maybe you can find a premade one?

Super Hans

Laptop PSU's tie the SMPS ground  to safety ground (earth). It is a loop. The problem is its a filthy loop.

I would make a box with in and out plugs, and use a Schurter DENO on the ground. You could use a metal outlet box, 2ft 12ga cord, two marinco ends. Connect safety ground to the box and DENO at thr same point, and then connect the DENO to the output safety ground. You don't even have to strip the hot/neutral inside the box at all, just do an open-ground surgery.

That is how I'd do it, but maybe you can find a premade one?
yes, same with PC. I tried it same way. Not UPS or anything in between. My uneducated guess is I need to run a Ground ext Cord from a Grounded Outlet, to all my Laptop/PC gear. 

Super Hans

I just went and bought a grounded ext. cord. plugged that into laptop. Problem resolved. Very happy.
Doesn't matter what the amp or DAC are plugged into, all noise is gone.
naturally the closest grounded outlet is 50ft away.
Breaker box is 30ft-40ft away, but in a good location. I can have an electrician run a grounded wire to grounded outlet. I think it would EZ-PZ to run the wire. You can see the backside of the wall to my main listening room in the basement. And I plug in my equipment to the wall you can see. With a flashlight you might be able to see the actual outlet.  It's under some storage shelves.  Really hoping it doesn't cost too terribly  much to run a 30ft-40ft grounded wire from breaker box to grounded outlet. 
Any suggestions appreciated :)

Thanks All !

DaveC113

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I just went and bought a grounded ext. cord. plugged that into laptop. Problem resolved. Very happy.
Doesn't matter what the amp or DAC are plugged into, all noise is gone.
naturally the closest grounded outlet is 50ft away.
Breaker box is 30ft-40ft away, but in a good location. I can have an electrician run a grounded wire to grounded outlet. I think it would EZ-PZ to run the wire. You can see the backside of the wall to my main listening room in the basement. And I plug in my equipment to the wall you can see. With a flashlight you might be able to see the actual outlet.  It's under some storage shelves.  Really hoping it doesn't cost too terribly  much to run a 30ft-40ft grounded wire from breaker box to grounded outlet. 
Any suggestions appreciated :)

Thanks All !

Good to hear... I'd go with 10g romex, 20A breaker and a Furutech GTX(R) receptacle... NCF if possible, if not there are many good deals on the previous non-NCF version.

Speedskater

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 The electrician can't just run a ground wire. But Romex® is the way to go. 10AWG with 20 Amp breaker if it's an easy run for a larger hi-fi system. For a smaller hi-fi and a challenging run 12AWG or even 14AWG (15 Amp) is OK.

Super Hans

My Cheap and Cheerful solution for now is running 3 prong extension cord from washer/dryer area to the Ethernet/cable TV outlet behind listening room. Unscrewed outlet plate and pulled cord through. It's less than 50ft. Feels like a somewhat ghetto solution but it was one of those things where, when I moved the mouse around it would make horrible hiss/static noises. Ext. cord runs along ceiling with other wires in unfinished part of basement, so it's not too super ghetto I guess. I checked all the outlets in this house with a gfci tester and the only grounded outlets are in the bathrooms and kitchen, of course. And the one in the basement by washer is fortunately grounded. I'm guessing most people don't want to pay the extra $ to get all the outlets grounded in a house. Horrible static/hiss is gone = me happy camper. Thanks for the Replies !

« Last Edit: 1 Jul 2017, 02:44 pm by Super Hans »

jea48

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It's not the ground, it's the loop area that may be the problem. But ground loops are about low frequency hum & buzz, not  hiss, noise & static.
Getting all the involved 3 wire chassis's connected together with short heavy wires is a good first step.
The 2 main problems are:
1] Internet, cable TV and remote PC's that are grounded elsewhere.
2] Poorly designed audio input connectors.
* * * * * * * * * * * *
While hiss, noise & static may be poor shielding or other interference problems.

I agree.

I just went and bought a grounded ext. cord. plugged that into laptop. Problem resolved. Very happy.
Doesn't matter what the amp or DAC are plugged into, all noise is gone.
naturally the closest grounded outlet is 50ft away.
Breaker box is 30ft-40ft away, but in a good location. I can have an electrician run a grounded wire to grounded outlet. I think it would EZ-PZ to run the wire. You can see the backside of the wall to my main listening room in the basement. And I plug in my equipment to the wall you can see. With a flashlight you might be able to see the actual outlet.  It's under some storage shelves.  Really hoping it doesn't cost too terribly  much to run a 30ft-40ft grounded wire from breaker box to grounded outlet. 
Any suggestions appreciated :)

Thanks All !

So why?  What possibly could the addition of the equipment ground be doing to solve the OP's noise problem?

Could it possibly be draining off any AC leakage that may be present on the chassis, from a power transformer, of a piece of equipment back to the main service neutral in the electrical panel? Thus putting the AC leakage on the chassis at zero potential with respect to the service neutral conductor? We both know it has nothing to do with mother earth.



Note this post of the OP's.
Quote
My Cheap and Cheerful solution for now is running 3 prong extension cord from washer/dryer area to the Ethernet/cable TV outlet behind listening room.
Cable TV.


   

Super Hans

The Cable TV cable is completely separate from everything else. Just goes to DVR/TV box for TV. I don't have it hooked to my main audio system in any way. Power for TV and DVR/TV box are separate too. This is not my main movie room so it's just the TV speakers for TV audio in this room. 

jea48

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The Cable TV cable is completely separate from everything else. Just goes to DVR/TV box for TV. I don't have it hooked to my main audio system in any way. Power for TV and DVR/TV box are separate too. This is not my main movie room so it's just the TV speakers for TV audio in this room.

So are you saying they are not plugged into the same AC outlet as your audio only system.
They are fed from an entirely different branch circuit.


Super Hans

So are you saying they are not plugged into the same AC outlet as your audio only system.
They are fed from an entirely different branch circuit.
I unplugged everything just as a process of elimination and only when I eliminated the power to the laptop did all the hiss and static go away. As soon as the laptop was running on it's own battery with no power cable plugged in, it works perfect. Then when I plug power cable back into laptop the hiss and static starts. Not positive if TV outlet and audio system outlets are same branch or not. I have unplugged TV, DVR box and still had static/hiss in the audio system. Just got done hanging ext. cord with cup hooks in basement. Fortunately everything is in convenient locations so it was less than 5 min job.

I'm still figuring out house electrical 'stuff'. I have the dac and amp plugged into a UPS/surge protector since I want them protected. The way I have it now with no static or hiss is: laptop into grounded ext. cord, and dac and amp into UPS/surge plugged into regular ole 2 prong outlet. 
« Last Edit: 1 Jul 2017, 10:55 pm by Super Hans »

Speedskater

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So why?  What possibly could the addition of the equipment ground be doing to solve the OP's noise problem?
Could it possibly be draining off any AC leakage that may be present on the chassis, from a power transformer, of a piece of equipment back to the main service neutral in the electrical panel? Thus putting the AC leakage on the chassis at zero potential with respect to the service neutral conductor? We both know it has nothing to do with mother earth.
......................   
In a word:
Yes