SMPS and grounding

[charlesphoto]

37 minutes ago, Em2016 said:

 

Hi,

 

Only asking out of interest but do we know for sure if the grounded AC input is actually doing what we want (shunting the high impedance leakage)?

 

For example, we know from what John's said that using a grounded DC output SMPS with any old switch is no guarantee to shunt these high impedance leakage currents, so he recommended a few that do work after he tested them.

 

And measuring/testing is not really something that any one of us can do - I did ask if I can just get a digital multimeter to check continuity and John told me that with ethernet switches it's more complicated than that.

 

Of course the fiber will block all leakage between switches but the most downstream switch MAY not shunt the high impedance leakage into the microRendu? Maybe it does.

 

Just thinking out loud. Maybe your switch does work but I'm not sure there's any way to know with certainty, other than trusting your ears.

 

 

Well, i wouldn’t overthink things too much. Just relaying what I’ve learned, and now heard (albeit having to trust my own ears) about commercial grade switches (the 2690-8TC-L in particular) vs consumer. John Swenson may be a guru, but he’s not a god. I think he gives great advice and knowledge on here, but he can’t know all, hear all, so you’ll have to find your own way. I am fortunate that within a very short confine, I’m able to have my gear on different circuits, so not as concerned about SMPS in the system. There are so many chargers, appliances, computers, led lights, dimmers, etc etc in this house that a few more aren’t going to hurt. And the commercial grade Cisco’s are about way more than the power. I’d be curious to hear John’s take on these units. I’m also beginning to think that one might be able to shunt the noise on an inferior device, but so what if the better non-shunted device just plain old sounds better? Your last sentence is the operative one - trust your own ears. No forum or magazine article could ever replace that. 

 

I do know of one Naim forum member who’s gone back to the shunted Netgear from the Cisco. In his system and room the bass became overwhelming. Which is exactly what I needed for mine. So best to experiment. And these things don’t cost much - both of mine looked practically new, for $29 ea - compared to big box gear purchases, and can make a nice uptick in sound for pennies compared to those. And I’ve had Netgear GS108, FS105, Trendnet, D-Link, etc, shunted, non-shunted, with and without linear power supplies, and my system is sounding the best and most natural now than it ever has. 

[wwc]

I use a Cisco Catalyst 2960 - C Switch-- un-shunted.   I also have the Netgear FS105, though I haven't compared it yet.

Have you tried the 2960 shunted?

[charlesphoto]

8 hours ago, wwc said:

I use a Cisco Catalyst 2960 - C Switch-- un-shunted.   I also have the Netgear FS105, though I haven't compared it yet.

Have you tried the 2960 shunted?

 

??? You can’t shunt them - they have a grounded AC iec input already. 

[Freann]

Curious of the JSSG thing, I decided DIY an ethernet version. 

(Don’t know if something similar has already been posted).

 

Example below is a generic cat7 cable with individually foil shielded pairs. 

1. First off, carefully remove the metal sheilding around the connector. 
2. Then remove 10mm or so of the outermost isolation. 
3. Now cut the screening braid at the connector end. Twist together and attach a small cable.
4. Repeat at other end 

 

I’ve now done this to all my ethernet cables. Each one gave a small but immediate improvement with increased clarity and more well defined soundstage. All together quite an improvement. Nice!

 

[luisma]

@JohnSwenson or @Superdad

Maybe this has been answered before but I could not find it in the thread.

The shunting technique, very good and understandable for simple devices like DAC's, etc. 

 

Would you say it is also acceptable to use this technique with NUCs? for example Intel NUC's with Fans etc. with a not grounded 19VDC adapters? 

 

I believe it should be safe but I'm not an EE and sending the - to ground may have other consequences of which I'm not aware of therefore my question to the experts to be safe

 

Thanks

 

Luis V

[Takacid]

On 9/20/2017 at 11:27 AM, JohnSwenson said:

Over the last month I have been performing extensive tests on leakage currents coming from SMPS power supplies. One of the most important results from this investigations is the makeup of this leakage current.

 

Previously my understanding was that leakage current was mainly a low frequency phenoninum, 60Hz, and its harmonics (60, 120, 180, 240 etc). My early investigations seemed to show that this was true with some high frequency components from the switching operation, but that this was fairly small in comparison to the whole. This turned out to be not true. It turns out that SMPS leakage is very hard to measure, it consists of some VERY high impedance components, on the order of 300 Mega ohms and some much lower impedance components.

 

None of the standard electronics test equipment will properly measure this, there impedance is simply too low and drastically changes the signal while trying to measure it. My only option was to build my own ultra high impedance differential probe (around 10 Giga ohms) so I can measure leakage current directly (rather than its affect on other equipment).

 

Because of this ultra high impedance it turns out leakage current can go all kinds of places you don't think about. It turns out to be extremely difficult to block using normal techniques, the blocking device has to have over a giga ohm to significantly attenuate it, this is VERY tough to achieve.

 

It turns out the best way to deal with this high impedance part is to shunt it around the audio equipment, there is a very easy way to do this, ground the negative output of the SMPS. It seems that even SMPS that include a ground pin don't actually use it for anything. This sounds too simple, but it actually works. PLEASE do not under any circumstances  attempt to modify an SMPS to do this, this is DEADLY, DO NOT attempt!!!

 

Fortunately there is a real easy - inexpensive way to do this, it doesn't take any complex knowledge, I'm calling this the power supply grounding adapter, here are a couple pictures:

 

 

This consists of three items and some wire. The yellow item is a three pin AC power plug (shown is the US model), the black parts are male and female DC barrel connectors with screw connectors, no soldering necessary! Amazon has a whole bunch of places selling these for CCTV cameras. The spec is 5.5mm outside and 2.1mm inside. Most you will see will be this spec. The + of the male is wired to the + of the female and - on the male goes to - of the female. Look at the close up picture, in order for the wire to go straight across one of the connectors has to be upside down. This is extremely important to get right. You can use many different types of wire for this, I used solid core 14AWG wire with the insulation stripped off.

 

A green wire goes from the ground pin of the AC plug to the - pin of one of the connectors, strip a little off and just stick it in with the wire going between the two connectors, use a screwdriver to tighten the screws, you are done.

 

The green wire does NOT have to be a heavy duty high power wire. The SMPS are already designed to be double insulated so the AC cannot show up on the DC output, grounding it does not pose any electrical threat. I just used some nice silicon rubber wire I bought on Amazon, but really any green wire will do.

 

You plug the output of the SMPS into the "jack" side, and the "plug" side goes into where you would have plugged the SMPS. The AC plug goes into the SAME power strip or duplex outlet where you plugged in the SMPS. This is very important to properly shunt the high impedance part of the leakage current. If it goes into a different circuit you can wind up making it worse.

 

You should do this on every SMPS that is somehow electrically connected into your sound system. Some items may have different connectors such and Ethernet switches etc. There are a bunch of different adapters available that can convert the 5.5/2.1 to just about anything out there, you may need to use a pair of these.

 

You may ask "how effective IS this?"

 

Here are some graphs, the first is the leakage current of an SMPS, the second is with this adapter plugged in:

 

 

 

That is a significant reduction in leakage for a $10 shunt adapter.

 

If you want to get it all you will have to use something like the LPS-1 which will get rid of it all.

 

Have fun,

 

John S.

 

Hi John, very interesting. I'm using Synergistic Research's Grounding Block. http://www.synergisticresearch.com/isolation/ground-isolation/grounding-block/

Instead of the 3pin AC power plug above, could I just have the green wire connect to the Grounding Block? Thanks,

[barrows]

37 minutes ago, Takacid said:

Hi John, very interesting. I'm using Synergistic Research's Grounding Block. http://www.synergisticresearch.com/isolation/ground-isolation/grounding-block/

Instead of the 3pin AC power plug above, could I just have the green wire connect to the Grounding Block? Thanks,

Is the Synergistic Grounding block actually grounded to AC ground?  I would confirm that it is, and then use it.  if it provides a "virtual" ground as some of these audiophile devices do., then I would not use it for this purpose.

[Cornan]

On 2018-05-16 at 6:15 AM, barrows said:

Is the Synergistic Grounding block actually grounded to AC ground?  I would confirm that it is, and then use it.  if it provides a "virtual" ground as some of these audiophile devices do., then I would not use it for this purpose.

 

Sorry, but as a person that have actually tried grounding boxes with JSGT IRL I have a different opinion! The opposite to be precise! ?

[luisma]

After reading all 39 pages and looking on how this relates to my specific equipment this is what I have had summarized, any feedback will be appreciated as I'm still a little confused with all these. If I misquote you John @JohnSwenson my apologies.

 

JSSG: John's Swenson Shielding Guidelines. 

• Applies to shielded DC or DATA cable where the shield is connected to the end connectors but not in loop. The technique basically states the entire shield should be connected at both ends together creating a loop with the use of auxiliary cable loop.

JSGT: John's Swenson Ground Tweak

• It applies to SMPS's which are feeding and fed back to/from "dirty" mains and basically flushes the negative - post of the SMPS output back to ground and NOT to the main.

 

And following the thread's previous discussions, and Alex @Superdad your comments are more than welcome here.

 

In case of having an LPS1.2 (or JS2)

• Input to the LPS1.2 from SMPS's if purchased directly from Uptone's is already shunted at the SMPS as these are custom designed to Uptone's specifications. No need to shunt.
• Output of the LPS1.2 feeding any equipment DAC, Ultrarendu, Allo Bridge etc. even through the use of a Y DC cable in which the LPS1.2 may be powering more than 1 device doesn't need to be shunted either as the LPS1.2 provides "clean" output power.
• DC cables connecting the LPS1.2 to equipment don't need shielding to improve SQ (and not shunting therefore as there is no shield) This one specifically I'm not so sure, shielding the DC output may improve things? I don't know.

These are specific to my existing setup which is Intel NUC connected via network and switch to Allo Bridge+Sparky connected to Pro-ject S2 DAC via USB cable connected to Yamaha AS2100 via analog interconnects Connected via speaker wire to Klipsch P37F, also analog interconnect to Powersound S3600 sub.

 

• Specific to the Allo Bridge/Sparky powering from 2 power supplies. The LPS1.2 powers the bridge which is connected internally electrically to the Sparky. An SMPS iPower 5V feeds the sparky. Should the SMPS connection into the sparky be shunted electrically with an adapter sending the - to ground? or since the LPS1.2 is already by design shunted and feeding the bridge then no need to shunt the SMPS powering the Sparky?
• If network switch is used to connect network streamers etc. the DC power coming to the switch should be shunted with JS adapter and the network cables should be shunted with the looping cable at the ends of the shield.
• If DC SMPS NUC PC is used the DC plug going into the NUC should be shunted to ground.
• Ethernet cables and usb data cables should be always shielded whenever possible and shunted.
• Analog interconnects should be shielded and shunted.
• DC cables don't need to be shielded 
• Speaker cables need to be shielded and shunted?

Like I said I don't want to create any confusions and comments are welcomed

 

Luis V

 

 

 

[charlesphoto]

Luis V.: 

 

One point: many of us have now discovered a huge bump in sound quality using Supra CAT8 (or other CAT7) as a dc cable. The extra shielding seems to be doing something pretty incredible. I think my LPS-1 was seriously throttled, even with very good Canare starquad, and sounds extraordinary with the Supra CAT8 cables I’ve made. So, yes, dc cables need shielding. Speaker cables no. Switch it all depends on the switch. I use Cisco 2960’s that have an internal SMPS and beat the pants off of any shunted consumer unit I’ve tried.  Stay tuned: streaming audio is a moving target to say the least. 

[luisma]

Thanks for the reply, something to consider indeed. You are using fiber optics and funny thing I have some recent experience with fiber optics  and RFI which I will be sharing in upcoming post on this forum., how this affects audio if it does I don't know

[luisma]

This kind of relates to this discussion although the effects have to be tested, I haven't had time to test with my system. and my intention is not to hijack the thread just provide some more constructive info.

 

Recently I have been involved designing radio public safety systems for many of these you need to establish fiber optic links between buildings and transmit data between these, for this you use single mode fiber mainly. This is all off the shelf technology.

 

I experienced a conflict with the fiber media converters and radio equipment, if you take a spectrum analyzer and you take RFI readings in about 1 MHZ channel at 812.50 MHZ (meaning you scan from 812 to 813 MHZ) and you turn on and connect via fiber two fiber media converters you will see a spike of 40 - 50 dbm in that channel, now I know we are discussing electricity here but in radio terms 40 dbm is A LOT in power, moreover you move away from the fiber media converter 150 ft and you still see this spike, if you unplug the fiber the spike goes down. I'm not an electrical engineer but I think to modulate and convert from data on copper to wavelength over fiber (1320nm I believe) you need an oscillator and this oscillator is the one that uses 812.5 MHz to modulate.

Of course if you are installing radio systems this "tone" is a BIG issue therefore I purchased about 20 different brands of fiber media converters, switches, routers, SFPs to transmit data over fiber and used my spectrum analyzer to find out the effects.

With all due respect to the manufacturers and without wanting to trash their products I am not mentioning who but out of these 20 plus devices I tested only 2 or 3 came out with minimal effects on the RFI transmitted. These 3 devices are using SFPs (self plugged fiber modules) and I believe the minimal effects are due to the shielding quality of the device itself.

If you are using 2 media converters on close proximity the effects are amplified.

Now I don't know if 812.5 (give or take) induces anything in music hifi related equipment, it may be harmless, if I have the time I have around 8 media converters I could not use for production which are perfectly functional and I may test and see if I hear any differences but my setup is still due to be finished.

One more thing, I used Reynolds thick aluminum foil to shield the entire switch or fiber media converter, I used 3 layers of same aluminum foil multiple wrapping to shield, I purchased copper shielding thick tape to block the RFI, the spectrum analyzer showed no changes, I believe I still have some videos, aluminum and copper foil don't do anything to RFI, maybe attenuated 2 - 3 dbm out of the 50 which is nothing and of course is not practical as these devices need proper ventilation to function. I did not used a faraday cage, I put everything inside a stainless steel grounded case which became an antenna after doing so. Even the DC adapter cable became an RFI emitter. 

 

I thought I should share this as it might or might not impact the setups with data fiber optics, don't know if you analyze the electrical impulses in speaker wire and interconnects if 812.5 mhz is a critical frequency.

 

Oh I forgot to mention, some fiber media converters not only created that spike, it also brought up the entire noise floor from 800 - 850 mhz for about 15 - 20 dbm so the effects may be amplified with one equipment or another.

 

I'll try to test and see if I can provide some real feedback, 

 

 

 

 

[JohnSwenson]

2 hours ago, luisma said:

After reading all 39 pages and looking on how this relates to my specific equipment this is what I have had summarized, any feedback will be appreciated as I'm still a little confused with all these. If I misquote you John @JohnSwenson my apologies.

 

JSSG: John's Swenson Shielding Guidelines. 

• Applies to shielded DC or DATA cable where the shield is connected to the end connectors but not in loop. The technique basically states the entire shield should be connected at both ends together creating a loop with the use of auxiliary cable loop.

JSGT: John's Swenson Ground Tweak

• It applies to SMPS's which are feeding and fed back to/from "dirty" mains and basically flushes the negative - post of the SMPS output back to ground and NOT to the main.

 

And following the thread's previous discussions, and Alex @Superdad your comments are more than welcome here.

 

In case of having an LPS1.2 (or JS2)

• Input to the LPS1.2 from SMPS's if purchased directly from Uptone's is already shunted at the SMPS as these are custom designed to Uptone's specifications. No need to shunt.
• Output of the LPS1.2 feeding any equipment DAC, Ultrarendu, Allo Bridge etc. even through the use of a Y DC cable in which the LPS1.2 may be powering more than 1 device doesn't need to be shunted either as the LPS1.2 provides "clean" output power.
• DC cables connecting the LPS1.2 to equipment don't need shielding to improve SQ (and not shunting therefore as there is no shield) This one specifically I'm not so sure, shielding the DC output may improve things? I don't know.

These are specific to my existing setup which is Intel NUC connected via network and switch to Allo Bridge+Sparky connected to Pro-ject S2 DAC via USB cable connected to Yamaha AS2100 via analog interconnects Connected via speaker wire to Klipsch P37F, also analog interconnect to Powersound S3600 sub.

 

• Specific to the Allo Bridge/Sparky powering from 2 power supplies. The LPS1.2 powers the bridge which is connected internally electrically to the Sparky. An SMPS iPower 5V feeds the sparky. Should the SMPS connection into the sparky be shunted electrically with an adapter sending the - to ground? or since the LPS1.2 is already by design shunted and feeding the bridge then no need to shunt the SMPS powering the Sparky?
• If network switch is used to connect network streamers etc. the DC power coming to the switch should be shunted with JS adapter and the network cables should be shunted with the looping cable at the ends of the shield.
• If DC SMPS NUC PC is used the DC plug going into the NUC should be shunted to ground.
• Ethernet cables and usb data cables should be always shielded whenever possible and shunted.
• Analog interconnects should be shielded and shunted.
• DC cables don't need to be shielded 
• Speaker cables need to be shielded and shunted?

Like I said I don't want to create any confusions and comments are welcomed

 

Luis V

 

 

 

Hi Luis,

 

the JSSG is a way to make cable shielding work at low frequencies. If you have a cable with a shield and don't use JSSG it will shield at high frequencies , but not low frequencies. ALL audio frequencies are considered low in this regard. Leakage current from SMPS are also considered low frequency.  Shielding can be keeping stuff from getting in and also for preventing stuff from coming out.

 

In order to figure out what needs to be properly shielded think about what the cable is for and what flowing through it. For example:

 

audio interconnect: high impedance analog signals, JSSG keeps the cable from picking up low frequency external signals, this is usually a very good thing for audio.

 

Ethernet cable: probably not too much affected by picking up low frequency signal, BUT leakage from SMPS powered LAN equipment can be radiated from the cable. JSSG prevents that from happening. Another way to deal with this is to go with the special switch that shunts SMPS leakage, so downstream of the switch there is no leakage on the Ethernet cable so the JSSG is not needed.

 

USB cable: can also radiate leakage current. If there is SMPS leakage going through the cable then JSSG will prevent that from radiating. If the USB source is powered from a LPS-1.2 there will be no leakage into the device from the power supply, but there still can still be leakage coming in over the Ethernet port. Using the special switch approach blocks that. In that case (no leakage going into device from PS and no leakage coming in from any other input) you do not need JSSG on USB cable. If any of that is violated then JSSG on USB will help.

 

So for any set of connected devices run this through the stsem, if the PS powering the device does not have leakage, and all inputs do not have leakage, you do not need JSSG on an output cable unless that cable is carrying a low level sensitive signal (like analog audio signals)

 

When "walking the tree" applying the above from device to device, the special switch (with appropriate power supply) blocks up stream leakage so you do not need to traverse further up stream.

 

Does this help?

 

John S.

 

 

 

 

[luisma]

4 hours ago, JohnSwenson said:

Hi Luis,

 

the JSSG is a way to make cable shielding work at low frequencies. If you have a cable with a shield and don't use JSSG it will shield at high frequencies , but not low frequencies. ALL audio frequencies are considered low in this regard. Leakage current from SMPS are also considered low frequency.  Shielding can be keeping stuff from getting in and also for preventing stuff from coming out.

 

In order to figure out what needs to be properly shielded think about what the cable is for and what flowing through it. For example:

 

audio interconnect: high impedance analog signals, JSSG keeps the cable from picking up low frequency external signals, this is usually a very good thing for audio.

 

Ethernet cable: probably not too much affected by picking up low frequency signal, BUT leakage from SMPS powered LAN equipment can be radiated from the cable. JSSG prevents that from happening. Another way to deal with this is to go with the special switch that shunts SMPS leakage, so downstream of the switch there is no leakage on the Ethernet cable so the JSSG is not needed.

 

USB cable: can also radiate leakage current. If there is SMPS leakage going through the cable then JSSG will prevent that from radiating. If the USB source is powered from a LPS-1.2 there will be no leakage into the device from the power supply, but there still can still be leakage coming in over the Ethernet port. Using the special switch approach blocks that. In that case (no leakage going into device from PS and no leakage coming in from any other input) you do not need JSSG on USB cable. If any of that is violated then JSSG on USB will help.

 

So for any set of connected devices run this through the stsem, if the PS powering the device does not have leakage, and all inputs do not have leakage, you do not need JSSG on an output cable unless that cable is carrying a low level sensitive signal (like analog audio signals)

 

When "walking the tree" applying the above from device to device, the special switch (with appropriate power supply) blocks up stream leakage so you do not need to traverse further up stream.

 

Does this help?

 

John S.

 

 

 

 

Thank you John for the detailed answer, it does help to clarify indeed, so does it harm to use JSSG cables (with shield and loop) even when these are not needed?

[lmitche]

17 hours ago, JohnSwenson said:

Hi Luis,

 

the JSSG is a way to make cable shielding work at low frequencies. If you have a cable with a shield and don't use JSSG it will shield at high frequencies , but not low frequencies. ALL audio frequencies are considered low in this regard. Leakage current from SMPS are also considered low frequency.  Shielding can be keeping stuff from getting in and also for preventing stuff from coming out.

 

In order to figure out what needs to be properly shielded think about what the cable is for and what flowing through it. For example:

 

audio interconnect: high impedance analog signals, JSSG keeps the cable from picking up low frequency external signals, this is usually a very good thing for audio.

 

Ethernet cable: probably not too much affected by picking up low frequency signal, BUT leakage from SMPS powered LAN equipment can be radiated from the cable. JSSG prevents that from happening. Another way to deal with this is to go with the special switch that shunts SMPS leakage, so downstream of the switch there is no leakage on the Ethernet cable so the JSSG is not needed.

 

USB cable: can also radiate leakage current. If there is SMPS leakage going through the cable then JSSG will prevent that from radiating. If the USB source is powered from a LPS-1.2 there will be no leakage into the device from the power supply, but there still can still be leakage coming in over the Ethernet port. Using the special switch approach blocks that. In that case (no leakage going into device from PS and no leakage coming in from any other input) you do not need JSSG on USB cable. If any of that is violated then JSSG on USB will help.

 

So for any set of connected devices run this through the stsem, if the PS powering the device does not have leakage, and all inputs do not have leakage, you do not need JSSG on an output cable unless that cable is carrying a low level sensitive signal (like analog audio signals)

 

When "walking the tree" applying the above from device to device, the special switch (with appropriate power supply) blocks up stream leakage so you do not need to traverse further up stream.

 

Does this help?

 

John S.

 

 

 

 

Hi John,

 

Despite use of the Netgear switch, two lps1s, and an ISO Regen there is still a benefit from jssg here for both usb cables, dc cables and ethernet cables.  Any idea what is going on?

 

Thanks,

 

Larry

[lvc10000]

Thanks Luis for the recap as I had missed the JSSG. And thanks to John for sharing. Will look into it for my Sonore DC + mini USB stub cables of my LPS-1 & Rendu. Awesome stuff.

 

I was just about to try to slip on some steel braided shielding over my preferred sata cables (ordered last week) to check it out but now am thinking about adding a wire linking both ends of the shielding under the heat wrapping to JSSG it.

Worth a try ?

[luisma]

All credit to JS @JohnSwenson for his contribution and sharing "freely" his knowledge and advice on these matters

[luisma]

19 minutes ago, lvc10000 said:

Thanks Luis for the recap as I had missed the JSSG. And thanks to John for sharing. Will look into it for my Sonore DC + mini USB stub cables of my LPS-1 & Rendu. Awesome stuff.

 

I was just about to try to slip on some steel braided shielding over my preferred sata cables (ordered last week) to check it out but now am thinking about adding a wire linking both ends of the shielding under the heat wrapping to JSSG it.

Worth a try ?

I assume the SATA cables are between a mini PC and external HDD? or you are trying to shield internal SATA cables?

 

I believe you meant to say USB, SATA transmits data and power and I don't really think you can loop the data on SATA without further effects to data transmission at 3 / 6 gbps

[lmitche]

23 minutes ago, lvc10000 said:

Thanks Luis for the recap as I had missed the JSSG. And thanks to John for sharing. Will look into it for my Sonore DC + mini USB stub cables of my LPS-1 & Rendu. Awesome stuff.

 

I was just about to try to slip on some steel braided shielding over my preferred sata cables (ordered last week) to check it out but now am thinking about adding a wire linking both ends of the shielding under the heat wrapping to JSSG it.

Worth a try ?

Yes worth a try. You could try it both ways as well, with and without the loop wire.

[lvc10000]

It was for "internal" satas that I was looking at improving the shielding ->  if I had a PC case and cramed it all in a small space like most would. So disk(s) power are on separate cables in direction of the power supply, away from the satas.

 

Thanks for the feedback guys. I'll give it a try and check it for myself.

[luisma]

On 1/5/2018 at 4:54 PM, octaviars said:

 

No problem 

 

This is how it looks when I got it connected in my cabinet. 

 

 

Ghent Canare 4S6 DC cables and Ghent ET02 ethernetcables. 200W HD Plex feeding 5vdc to ISP fiberconverter, 19vdc to router, 12vdc to GS108 switch (-0V grounded) 19vdc to NUC with Roon ROCK.

Endpoint is a SOtM SMS Ultra (PSU will be a Paul Hynes SR4 when it arrives, lost by UPS since 20th December).

 

@octaviars reading your post I noticed the NUC is not shunted -0 grounded, I have the same NUC and I have been asking if it is a good idea to do it. Any specific reason why?

Thanks

 

[luisma]

20 minutes ago, lvc10000 said:

It was for "internal" satas that I was looking at improving the shielding ->  if I had a PC case and cramed it all in a small space like most would. So disk(s) power are on separate cables in direction of the power supply, away from the satas.

 

Thanks for the feedback guys. I'll give it a try and check it for myself.

Let us know how it works when you do it 

[octaviars]

39 minutes ago, luisma said:

@octaviars reading your post I noticed the NUC is not shunted -0 grounded, I have the same NUC and I have been asking if it is a good idea to do it. Any specific reason why?

Thanks

 

 

I use a linear powersupply (4 rails) to power my network equipment and only ground the 12V rail that is feeding my Netgear switch to shunt noise on the network. Dont know if it will make any difference to ground any of the other -0V that feeds ISP fiberconverter, router and NUC.

[lvc10000]

2 hours ago, luisma said:

Let us know how it works when you do it 

 

Will do! 

[lvc10000]

Well, my feedback is not as I expected so I've continued testing a bit more before posting. In the last 4 weeks I've tried JSSGing Satas (System SSD & music storage HDD), the Sonore DC cable of my LPS-1 and the Sonore mini USB stub cable going to my MicroRendu. And I tried the PC with both linear & ATX power supplies.

For the 3 types of cables I tried, the findings in my system go in a similar direction. I was listening for a noticeable variation in distortion for example however in my case I keep coming back to a reduction of the top end information. And the more cables added, the results seems to add-up further in the same direction.

It is seductive with one cable in the loop in the sense that it brings out better focus to the medium and voices for example and fleshes out a bit further/more. However as counter example, a cymbal goes/tones down a notch, or for example a piano's wooden resonances information are reduced/hidden. Tough call.