Tuning Tip: Don't dress interconnects under Mains leads

Darke Bear posted:

Something I just discovered that had far more impact than I thought.

I had a SL interconnect lead from my CD555 source to the S1 Pre that looped through a gap between the power leads to my Analogue and Digital 555PS for it. It was well-clear of the mains cable by a few inches and free-hanging, so I thought it was OK - but when I decided to move the power lead underneath the Interconnect cable, in fact ending-up a bit closer, but under it - the step-up in performance was rather remarkable.

The system gained more immediacy and focus and timing was faster in a good way - everything clearer too. All good!

So many of us try to dress the leads and let them go wherever they seem to fit without fouling, that perhaps we are sacrificing performance without realising it. All I can think is that the magnetic fields with the IC lead running between two mains cables adversely impacts performance a lot more than the IC having free space all around it and just mains below it.

For those that are going to say it was contact-cleaning - I didn't unplug the lead, just re-routed it while still connected. When I listened again it was a 'wow' moment.

Some may find this useful.

DB.

what led you to try this tweak, DB?

i have just done a quick check and mine are all OK.

are you suggesting 'under' is bad vs 'over'  is better??? 

enjoy...

ken

Darke bear, it is my belief that you are as nutty as a box of nails. I do hope that beyond this never ending tweaking you do, you actually enjoy some music

Box of nails? I've always thought it was box of frogs.

Just not having the IC lead surrounded on all sides by mains leads as it threads in-between is what I mean.

A few weeks ago I 'tidied' my leads and didn't realise that I'd made it worse by what I'd done and been subliminally aware it was not performing as what I remembered it should, but not sure what it was that could be wrong.

It is not a light and day change - just a worthwhile improvement to be had.

Frogs or Nails are fine by me.

Just try putting the nails in with the frogs and see how many nuts you get then...

For cable dressing, try connecting headphones to your system and with no source playing, turn the volume up on the input where you are dressing the cable. You can hear the interference and tweak to the nth degree. Don't forget to turn the volume down again when you've finished! 

I wouldn't consider pulling and pushing plugs with everything powered up a very good idea.

Yes I follow the same principle for Ethernet cables as well, ie 90 degrees to signal leads.

"All I can think is that the magnetic fields with the IC lead running between two mains cables adversely impacts performance a lot more than the IC having free space all around it and just mains below it."

Wonder what the fieldstrength is.

And, of course, the 50Hz induction into the signal cable would have to be easily measurable.

Hi Jon, this is easily measurable of course with EM field meter.. and will vary with mains cable construction. Though I suspect the field strengths near a typical Naim system will be quite high anyway.

i think I would be more concerned about the HF noise on the mains coupling into the interconnects producing low level intermodulation effects. This is the analogue equivalent of digital noise and jitter and can sap the system of its vitality. (In my opinion)

Now what to do with speaker cables  .....  

"i think I would be more concerned about the HF noise on the mains coupling into the interconnects producing low level intermodulation effects."

Again, should be easily measured by a decent spectrum analyser. 

It could be something else entirely -- the enhanced oxygen flow to the brain caused by getting out of listening chair, walking to rack, leaning over, fiddling with cables, then sitting down again.

Mike, I guess with power cables because of the wavelength of the dominant wavelength, the screen in practical cables will not be that effective (for egress interference) because of near field effects. Higher wavelengths might better be impeded using a braided weave geometry of the mains cable, I believe Naim Powerline use such a weave.. but could be wrong.

Now my puzzlement with Naim is inside their  boxes.. here we see power bus cables routed in straight lines in parallel with each other. I was always taught this was a complete no-no if one wanted a high degree of decoupling between the power bus lines... the suggested way for increased decoupling is often to braid them so as to reduce near field coupling ... I can only assume Naim consider the cross modulation effects on SQ a lesser evil to whatever happens with Naim designs when they braid them.

Edit: John absolutely with of course an appropriate wide band EM receiver.. I don't have a descent enough spectrum analyzer in my mitts currently ... However I do use my digital oscilloscope with a simple coil receiver and you can see the HF hash / noise on the mains EM field.. and DC lines on cheap SMPS can be horrendous....

Simon-in-Suffolk posted:

Mike, I guess with power cables because of the wavelength of the dominant wavelength, the screen in practical cables will not be that effective (for egress interference) because of near field effects. Higher wavelengths might better be impeded using a braided weave geometry of the mains cable, I believe Naim Powerline use such a weave.. but could be wrong.

Now my puzzlement with Naim is inside their  boxes.. here we see power bus cables routed in straight lines in parallel with each other. I was always taught this was a complete no-no if one wanted a high degree of decoupling between the power bus lines... the suggested way for increased decoupling is often to braid them so as to reduce near field coupling ... I can only assume Naim consider the cross modulation effects on SQ a lesser evil to whatever happens with Naim designs when they braid them. 

Darke Bear posted:

Frogs or Nails are fine by me.

Surely if it's going to be a box of anything, it should be bears

Simon-in-Suffolk posted:

Mike, I guess with power cables because of the wavelength of the dominant wavelength, the screen in practical cables will not be that effective (for egress interference) because of near field effects. Higher wavelengths might better be impeded using a braided weave geometry of the mains cable, I believe Naim Powerline use such a weave.. but could be wrong.

Now my puzzlement with Naim is inside their  boxes.. here we see power bus cables routed in straight lines in parallel with each other. I was always taught this was a complete no-no if one wanted a high degree of decoupling between the power bus lines... the suggested way for increased decoupling is often to braid them so as to reduce near field coupling ... I can only assume Naim consider the cross modulation effects on SQ a lesser evil to whatever happens with Naim designs when they braid them.

 

Edit: John absolutely with of course an appropriate wide band EM receiver.. I don't have a descent enough spectrum analyzer in my mitts currently ... However I do use my digital oscilloscope with a simple coil receiver and you can see the HF hash / noise on the mains EM field.. and DC lines on cheap SMPS can be horrendous....

 

 

right, "show my ignorance time"...

what the wavelength of the dominat wavelength?

whats egress interference? and what impact does it hav n music?

power bus cables inside naim equip -- is that DC or otherwise?

sorry, noddy questions...

enjoy

ken

while onthe subject of "tweaking"/"tinkering" etc...

do you guys agree that these can be divided into at least 2 types:

- ones with 1st order effects (suppose thse are not really tweaks but important installation requirements)

- others with smaller to insignificant (2nd order and above)  effects - (the real "tweaks")

but coming to think of it, this may not get us that far given that often, we dont even agree on 1st order effects!

all the more strange that we all more or less agree that Naim hifi is great (unless one decides to sell it!) -- despite disagreements on little details.

sorry, waffling again...

enjoy

ken

Just checked but in my lesser passive system there are no such worries. Most of the PLs are well away from the ICs plugged into the brawn stack. Only the Radikal is plugged on the brain stack and, as it's placed low the PL is well away from the signal cables. Phew!

hi Ken - the dominant wavelength in the mains is associated with 50Hz (in Europe) which has a wavelength of 6000km! - but with say a 35MHz RF current on the mains - that will have a wavelength of approx 8.57 m. Wavelengths are important with respect to the electro magnetic near field which occurs within the first wavelength - but falls rapidly away exponentially in terms of strength over distance. However its the reactive near field (wavelength/(2*Pi)) that tends to couple with other devices which are intersecting or disrupting the near field. A transformer uses this property to function for example.. and is the property that permits unbalanced or in adequately shielded signal leads to couple with each other. It is also this property that  causes mains hum to be picked up in certain scenarios.

With egress interference i am referring to EMI emanating from the main lead.

Yes the power busses are the various DC power cables inside of the case. If you look you see often the power cables are routed in parallel to each other - and so any modulation on the DC line may couple to the other lines.

First world, first life, mortal problems. Ho hum!! 

I wouldn't consider pulling and pushing plugs with everything powered up a very good idea.

I think we all concur with that Gary.