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Ground loops

Unless you really need short cables, I'd suggest getting 1 m and/or 2 m cables and letting the extra lie loosely behind the components. Always a chance you'll move something later and discover that sweet, expensive, custom 0.25 m cable is useless. Don't ask how I know this...
I've not too worried about that, I've already got some old standard-length RCA cables laying around (somewhere around here, at least) from back when that's how you hooked your TV up. I just wanna get shorter cables to keep things tidy - I got enough cable clutter as it is!

A really good way to eliminate risk of ground loop in a simple system - especially one that is simply PC-Dac-Amp is to use an optical TOSLINK connection from PC to DAC. This fully breaks any electrical connection between the PC and the DAC.

If you don't have toslink out from your PC, cheap USB to toslink converters are available.
My PC hasn't got TOSLINK-out, no. Are there any in particular you'd recommend? I did see some on Amazon but I can't tell whether they'd be any good.

Whether I actually need to go down that road or not... I'll do my test when the amp and the RCA to 3.5mm get here, then go from there.
 
I said it is one reason, not the only one.
Really ??, ... not as far as I can see / read ???

You use computers?
Ahhh, no, am currently using a Chisel and a Rock I found outside earlier, and Posting my replies in,.. :p:D:):cool:
I did use a 'wink' on my statement,.. I was being facetious, but still best to Not use them, if (for your reason's) IF you don't have to !!

I have not checked this System with any equipment like Amir uses but it does not hum, I have no perceivable (visual or Audible) noise in Audio Programs with or without Laptop :)
This All In One unit, I am using now, is delightfully Quiet :cool:
 
Whether I actually need to go down that road or not... I'll do my test when the amp and the RCA to 3.5mm get here, then go from there.
YES !!! Absolutely,... Doom-Sayers begone lol,.. there is YET to even Be a Problem !! ;) :)
 
Really ??, ... not as far as I can see / read ???
example.png
 
Oh dear, please, let's not become painfully pedantic !!
I said it is one reason, not the only one
Referring to that as what you said, is NOT the same as:
To give one example
Nor is 'One Example' intrinsically the Same as 'One Reason' ...
I'm NOT interested IN or trying to argue with you or anyone.

The OP has yet to even Plug all his equipment in yet and already almost everyone other than myself has expressed all the Problems that will occur, before they have even happened !!

If the OP's post had suggested he had what he has and it has a hum and ground-loop, then great,.. but atm, it has Nothing !!
He's still waiting on cables !!
Let's see if any Hum dragons raise their heads first eh ??

I was simply trying to suggest a simple method of best initial practice, not to find a solution to an as yet non existent issue.

Leave it all with you OK
Cheers :)
 
Whether I actually need to go down that road or not... I'll do my test when the amp and the RCA to 3.5mm get here, then go from there.
Good plan - you'll probably be fine.

Regarding the USB to Toslink - they'll either work or not. No need to worry on impact to sound quality. If they work without clicks, pops or dropouts, then they are working perfectly.

I'd just get something that looks like this:
 
I've not too worried about that, I've already got some old standard-length RCA cables laying around (somewhere around here, at least) from back when that's how you hooked your TV up. I just wanna get shorter cables to keep things tidy - I got enough cable clutter as it is!
Extra length is also good if you need to move things around or pull things out to check connections. You could coil the excess and bundle with Velcro cable ties. I did that, and made separate bundles for audio, video, and power cables.
 
Extra length is also good if you need to move things around or pull things out to check connections. You could coil the excess and bundle with Velcro cable ties. I did that, and made separate bundles for audio, video, and power cables.
Never coil interconnect. You create an inductor in the ground conductor more capable of picking up noise from magnetic fields, especially transformers. Instead bundle them by "zigzagging" the interconnect. Here is a helpful, but not very good, sketch :)

Screenshot 2024-07-27 at 08.33.43.png
 
Never coil interconnect. You create an inductor in the ground conductor more capable of picking up noise from magnetic fields, especially transformers. Instead bundle them by "zigzagging" the interconnect. Here is a helpful, but not very good, sketch :)

View attachment 383264
I generally reverse coil in a figure 8 so magnetic coupling is cancelled, but with coax it really shouldn't matter much, save for those pesky magnetic fields. That said I have just coiled the "bad" way frequently behind my console, where the coils are at the top and all the big transformers on the bottom, so there is a fair amount of distance between. And I do not coil (in any configuration) audio, video, and power together if at all possible.
 
I generally reverse coil in a figure 8 so magnetic coupling is cancelled
Yes, ... same.
Have often had to use coils (in installation work), to provide ability to move / re-position equipment and/or re-terminate etc.
Never had a Single situation, where it caused any 'issue'.

but with coax it really shouldn't matter much, save for those pesky magnetic fields
Agreed but What Magnetic Fields are we thinking of and how close and strong are they ?? ;)
I'd venture other items in the system, would be similarly effected by these 'Stray' magnetic fields, not simply the Cables :)

One should never Flat Coil Power cables, especially if drawing decent current, as heat can build up and cause problems !!
Always BEST to lay the Excess out in a suitably large 'Figure-8' pattern.
 
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Never coil interconnect. You create an inductor in the ground conductor more capable of picking up noise from magnetic fields, especially transformers. Instead bundle them by "zigzagging" the interconnect. Here is a helpful, but not very good, sketch :)

View attachment 383264
Is ^that^ true?

They are a twisted pair, so it is not like the + side that is in a coil independent of the - side.
 
Agreed but What Magnetic Fields are we thinking of and how close and strong are they ??
One example is that around PSU transformers. Coupling will be proportional to the number of turns in the coil. I learned this by practical experience of hum picked up from the transformer of my amp.

But in reality any circuit will be generating a magnetic field proportional to the current in the circuit - this could be the wiring in your house**, or perhaps fields generated around a PC graphics card running at full tilt (many people hear graphics related noises in ground loops)

I think most cases of mains frequency hum in ground loops are from magnetic coupling.

** put your coil down the back of the system against a wall with a 32A ring circuit in it, separated only by 10mm of plasterboard. I'd be surprised if there wasn't some coupling there.
 
Is ^that^ true?

They are a twisted pair, so it is not like the + side that is in a coil independent of the - side.
The shield isn't a twisted pair - ground loops currents are in the shield. Plus, RCA isn't twisted pair - normally a single conductor inside the shield.
 
The shield isn't a twisted pair - ground loops currents are in the shield. Plus, RCA isn't twisted pair - normally a single conductor inside the shield.
OK - mine are a shield with a twisted pair inside.
The shield is only grounded on one RCA.

In any case, envision the shield as a twisted pair, with the twist so tight as to be come a solid shield.
There will be nothing inducted between the + and -, but I can see how the - side could work as a coil on its own.
 
One should never Flat Coil Power cables, especially if drawing decent current, as heat can build up and cause problems !!
Always BEST to lay the Excess out in a suitably large 'Figure-8' pattern.
While heat can build up in a tightly coiled AC power cord.
There is no need for a 'Figure-8' pattern.
There is no large field from an AC cord, because the 2 conductors cancel almost all of each others field.
 
I have discovered all the power lines passing through my floor (under concrete+thick granite tiles,lines in their one enclosures) only by measuring my rig with a 6 meter cable so to see what exactly does as-is at it's racks.

Cable I use is a very well made Mogami star Quad,balanced all the way,etc.
I can literally kill about 5-6dB of SINAD just by avoiding these lines (probably inaubible at it's 50Hz but still,visuals can stick in your head if you mess with measurements)

But even without measuring the rig,just shorted where the reported noise is at -113dB ,passing over these lines,coiling,etc has it's effects too.
 
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While heat can build up in a tightly coiled AC power cord.
There is no need for a 'Figure-8' pattern.
There is no large field from an AC cord, because the 2 conductors cancel almost all of each others field.
Sorry, you are completely Wrong my friend,.. or you have never been drawing serious current through any 240v cables !!
I have seen a fire start because of this and once managed to disconnect a very lengthy mains cable that had been coiled behind and under the Stage curtain, where the insulation had become So soft, it was starting to melt together,.. a few more minutes and trouble would have ensued !!!

Seriously I speak of what I know !!!
MANY years in the Live music arena,..
BTW, If as you suggest the 2 x conductors cancel each other's field, what are you actually suggesting ?? What 'field' and how does that field have anything to do with heat generated by current flow ?? ... Answer :)

Coiled Wire​

Electricity flowing through a wire creates a magnetic electric field current. You generally cannot see, hear or feel it. A coil of wire, such as an extension lead, increases the magnetic electrical field current. The result is the production of heat. The wire then gets hotter, making the outer plastic coating soft (and therefore weaker), which strengthens the electrical field, eventually causing the coating to melt.
I did say btw: "One should never Flat Coil Power cables, especially if drawing decent current, as heat can build up and cause problems !!" it was simply a precautionary warning regarding High current draw and Heat. ... Simple really.

Try it with 3-Phase lighting cables and see how long it takes to get dangerously HOT
 
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Has anyone suggested testing the wall outlets for correct wiring?
 
Sorry, you are completely Wrong my friend,.. or you have never been drawing serious current through any 240v cables !!
I have seen a fire start because of this and once managed to disconnect a very lengthy mains cable that had been coiled behind and under the Stage curtain, where the insulation had become So soft, it was starting to melt together,.. a few more minutes and trouble would have ensued !!!

Seriously I speak of what I know !!!
MANY years in the Live music arena,..
BTW, If as you suggest the 2 x conductors cancel each other's field, what are you actually suggesting ?? What 'field' and how does that field have anything to do with heat generated by current flow ??

Try it with 3-Phase lighting cables and see how long it takes to get dangerously HOT
+1
Once I asked about a very big price difference of the same length extension cable which is coiled around these circular rolls with a handle on top.
The electrician in the shop showed me the warning on the -plastic,cheap- one that was saying that it should be unrolled before any use.
The metallic one had a cert that it was shielded and good to work even unfolded.

Needless to say which one I got.
 
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Has anyone suggested testing the wall outlets for correct wiring?
NO,.. Why??
The OP, has yet to even 'Run' his System up,.. :)
There is so far NO problem of Any kind whatsoever,.. this is all theoretical disasters,.. LOL
 
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