Overall Isolation - network, USB, and power

[austinpop]

Hello all,

 

I've followed, with great interest, the explorations and findings reported here to improve sound quality in the area of isolation. These seem to fall into 3 categories: network, USB, and power, and they are mostly discussed in, well, isolation. However, in many cases, an improvement in one area can cause a degradation or worse, failure, in another.

 

I've tried to make sense of this in my system, and am finding myself somewhat confused. What I'm hoping with this thread is to get the experts here to discuss some of these trade-offs in the context of an overall system.

 

What do I mean by trade-offs? Before I get there, let me summarize the tenets of SQ improvement through digital audio isolation that I've gleaned here. This is by no means a complete list.

1. LPSes greatly improve SQ over stock SMPSes
   
2. Battery PSes can provide excellent SQ, while reducing the potential of ground loops
   
3. Network isolation using a pair of FMCs upstream of a DAC can improve SQ
   
4. The FMC closer to the DAC should have an LPS or battery pack for best SQ
   
5. Some advocate using a passive network isolator instead of FMCs
   
6. USB regeneration/reclocking via Regen/RUR/Intona can greatly improve SQ
   
7. Suppressing the USB 5V Vbus for some powered DACs (using Sbooster Vbus2, taping terminals, or using a 3-wire cable like Curious) can improve SQ
   

 

Here are some examples of trade-offs and gotchas:

1. Every PS, even an LPS, contributes noise back to the AC line
   
2. Adding FMCs also add power supplies, which could add noise (see 1)
   
3. Adding a USB reclocker requires another PS, which could add noise (see 1)
   
4. Connecting multiple devices to an LPS with multiple rails, can cause common ground situations that defeat isolation
   
5. 5V Vbus suppression can cause some devices to fail the USB handshake
   

 

To kick off this discussion, let me talk about some proposed optimizations in my system. Rather than waste a bunch of words describing, let me show a diagram of my current system:

 

 

And here are the proposed modifications (in green):

 

 

I think I've addressed the potential gotchas, but would like some expert opinions. Specifically:

• Could there be a potential issue powering both the Aries Mini and the Recovery from a single HDPlex LPS?
  
• Is the battery power on the FMC shown really necessary?
  
• Is the proposed Vbus location optimal? Should I consider another between the Aries Mini and the Recovery?
  

 

I look forward to your insights!

[Cornan]

Hi austinpop,

 

• Could there be a potential issue powering both the Aries Mini and the Recovery from a single HDPlex LPS?
  

It could. However, this highly depends on the quality and construction of the LPS. Both outputs needs to be isolated from each other. If it is or not would be a question for HDPlex. Also, different setups are much more sensitive to mains noises than others.

 

• Is the battery power on the FMC shown really necessary?
  

 

Not at all. The point of having battery power for FMCs are that both sender and receiver should be battery powered so it is "unvisable" for the AC mains. Another choise is to power both with a separate LPS in another wall outlet (ie. on a different mains fuse) than the remaining audio gears...which will atleast minimize noise problems (and almost remove it completely if connected to a good power filter with separate filters for each socket).

 

 

• Is the proposed Vbus location optimal? Should I consider another between the Aries Mini and the Recovery?
  

Optimal would really to use a Vbus2 between the Aries Mini & Recovery AND between Recovery & Ayre Codec DAC. Even if Recovery will provide clean 5v power nothing beats no power at all since it blocks all the noise from entering via the 5v lead...not just make it cleaner. Aries Mini also gain a lot from blocking the 5v IME.

[austinpop]

Hi austinpop,

 

Hi, @Cornan. Thanks for responding. Some of the thought that went into the topology came from your comments in a couple of other threads, for which I am grateful! I am hoping to get some more perspectives on this thread as well.

 

It could. However, this highly depends on the quality and construction of the LPS. Both outputs needs to be isolated from each other. If it is or not would be a question for HDPlex. Also, different setups are much more sensitive to mains noises than others.

 

Yes, I got the qualitative argument. But extending this argument, it would appear any LPS with more than one output rail is fraught with potential danger (pun intended). Yet, the universally acclaimed JS-2 exists with 2 rails. I'd like a little technical insight from experts like @JohnSwenson about what inter-rail isolation really means.

 

Not at all. The point of having battery power for FMCs are that both sender and receiver should be battery powered so it is "unvisable" for the AC mains. Another choise is to power both with a separate LPS in another wall outlet (ie. on a different mains fuse) than the remaining audio gears...which will atleast minimize noise problems (and almost remove it completely if connected to a good power filter with separate filters for each socket).

 

Something like this? See the picture below:

 

 

I pose the question in the diagram too, but - is using a BPS on both FMCs achieving the much-vaunted galvanic isolation? However, my simple-minded brain then asks: how do I know the potential of the battery's ground and that of the mains-powered LPS are the same? Am I not now creating a possible ground loop?

 

Optimal would really to use a Vbus2 between the Aries Mini & Recovery AND between Recovery & Ayre Codec DAC. Even if Recovery will provide clean 5v power nothing beats no power at all since it blocks all the noise from entering via the 5v lead...not just make it cleaner. Aries Mini also gain a lot from blocking the 5v IME.

 

I thought I read in the Recovery curated thread that the RUR needs the 5V on its input for proper operation.

[Cornan]

Hi, @Cornan. Thanks for responding. Some of the thought that went into the topology came from your comments in a couple of other threads, for which I am grateful! I am hoping to get some more perspectives on this thread as well.

 

 

 

Yes, I got the qualitative argument. But extending this argument, it would appear any LPS with more than one output rail is fraught with potential danger (pun intended). Yet, the universally acclaimed JS-2 exists with 2 rails. I'd like a little technical insight from experts like @JohnSwenson about what inter-rail isolation really means.

 

 

 

Something like this? See the picture below:

 

[ATTACH=CONFIG]29125[/ATTACH]

 

I pose the question in the diagram too, but - is using a BPS on both FMCs achieving the much-vaunted galvanic isolation? However, my simple-minded brain then asks: how do I know the potential of the battery's ground and that of the mains-powered LPS are the same? Am I not now creating a possible ground loop?

 

 

 

I thought I read in the Recovery curated thread that the RUR needs the 5V on its input for proper operation.

 

One thing that I would ask myself it how important those FMCs are for the overall SQ? Personally I am using strong 5G wireless network to the Aries Mini. The router input is galvantic isolated and the routers SMPS is connected to a power filter on a different mains fuse than my audio gears. Sounds very good but have'nt compared to anything other than Cat6, Cat6a and Cat7 Ethernet cables. Just a thought.

 

BPS does'nt brake the galvantic Isolation. Since FMCs creates a galvanicly isolated Ethernet you do not need to worry about creating ground loops.

 

I would connect the Aries to Zone 1, RUR & DAC to Zone 2 and AMP to Zone HC. The battery pack to a different mains fuse.

 

I also read somewere that the RUR needed to see 5v as well...but got corrected by several members who said that they actually can cut off 5v without a problem when using RUR.

 

/Micael

 

Sent from my Nexus 7 using Computer Audiophile mobile app

[austinpop]

One thing that I would ask myself it how important those FMCs are for the overall SQ? Personally I am using strong 5G wireless network to the Aries Mini. The router input is galvantic isolated and the routers SMPS is connected to a power filter on a different mains fuse than my audio gears. Sounds very good but have'nt compared to anything other than Cat6, Cat6a and Cat7 Ethernet cables. Just a thought.

 

Good question! This is one of the baffling aspects of SQ optimization. I in fact started by using the Aries Mini wireless, even using the opportunity to upgrade my WAP to a 802.11ac Asus unit. I also moved the WAP so that the Aries Mini would see a strong signal.

 

At some point I had some dropouts with DSD128 files, and thought I'd try wired ethernet. I was quite startled to hear a small but noticeable improvement in SQ. More recently, I added the FMC isolation. This added another layer of improvement, and to be honest, sounds very good, even with the Jameco wall warts.

 

I still cannot explain why this is happening. In fact, now the difference between wireless and my FMC isolated wired network is quite noticeable and wired is consistently better.

 

So in the same vein of not sure why, I say I am happy with the current PS, but I will not be the least bit surprised if the battery PS yields another quantum of SQ improvement.

 

There is no end to this tweaking!!

[lmitche]

The reason that network isolation is important is quite simple. Your cable modem, router and through them the entire network is connected to the cable system running to your house. The cable system is destined to carry radio frequency signals. That is its purpose. But past your cable modem, you don't want any RF. Despite galvanically isolated ethernet connections, the RF will carry into your network cable plant. Also long cable runs may pickup RF and EMI from in home AC cables or whatever. An Ethernet isolation device, fiber or transformers stops, or lowers, the pollution. I have four on my network.

[davide256]

In the FWIW column I found that with Aries mini powered by HDPlex LPS I preferred AQ Eagle Eye coax for accuracy vs using asynch USB converters to external PCM DAC. Converters used were Gustard U12 and iFi Nano. I sold the Aries mini before I setup optical Ethernet, suspect that some of the reasons I sold it now were due to wired/wireless Ethernet noise and jitter limitations, that optical Ethernet would have helped greatly as it did with the microRendu.

[austinpop]

The reason that network isolation is important is quite simple. Your cable modem, router and through them the entire network is connected to the cable system running to your house. The cable system is destined to carry radio frequency signals. That is its purpose. But past your cable modem, you don't want any RF. Despite galvanically isolated ethernet connections, the RF will carry into your network cable plant. Also long cable runs may pickup RF and EMI from in home AC cables or whatever. An Ethernet isolation device, fiber or transformers stops, or lowers, the pollution. I have four on my network.

 

Larry, all fair points with regard to pollution on the wired network, and the positive impact of isolation.

 

But since wifi (802.11ac, 5GHz, strong signal) has complete network isolation, I'm still not sure why it still sounds worse than wired - even with adequate bandwidth. Yet it does. Many people have reported superior SQ with wired over wireless for Aries and Aries Mini streamers.

[austinpop]

In the FWIW column I found that with Aries mini powered by HDPlex LPS I preferred AQ Eagle Eye coax for accuracy vs using asynch USB converters to external PCM DAC. Converters used were Gustard U12 and iFi Nano. I sold the Aries mini before I setup optical Ethernet, suspect that some of the reasons I sold it now were due to wired/wireless Ethernet noise and jitter limitations, that optical Ethernet would have helped greatly as it did with the microRendu.

 

At some point, I'd love to compare the mRendu with the Aries Mini in my setup. Since I have zero interest in Roon, HQPlayer etc, I'd be comparing both as UPnP streamers, and I'm not sure how much better the mR will be.

 

Right now, I'm having more fun tinkering with isolation and USB reclockers!

[lmitche]

Larry, all fair points with regard to pollution on the wired network, and the positive impact of isolation.

 

But since wifi (802.11ac, 5GHz, strong signal) has complete network isolation, I'm still not sure why it still sounds worse than wired - even with adequate bandwidth. Yet it does. Many people have reported superior SQ with wired over wireless for Aries and Aries Mini streamers.

My music network has a wireless connection to a router sitting 6 inches away. The router creates a second subnet on one end of the home network. An El Cheapo powered Asus ea-n66 wireless adapter is connected to my NAS PC with an EMOsystems isolation transformer between two BJC CAT 6a cables. This way the wireless connection only carries the ROON iPad control signals and internet connectivity for the NAS PC and downstream audio PC.

 

The NAS PC has two nic ports, one connected to the wireless adapter as described above and the second direct to the audiopc (with another isolation transformer & BJC Cat 6as). A virtual switch in the NAS routes traffic, so no physical switch or power supply is used.

 

With the isolation transformer, no pollution from the wireless adapter is evident. Lastly the music signal always passes on a wired connection. This is a good thing.

 

After spending close to a year testing any number of network and isolation configurations, fiber FMCs etc, this is what sounds best here.

[austinpop]

Wow, that's some topology!

[lmitche]

Wow, that's some topology!

Lol, I'm not sure that's a compliment. It is certainly the first time my toplogy has raised a Wow.

 

The music network is as simple as I could make it with only five active components in a line: wireless adapter, NAS PC, Audio PC, DAC and Amp.

 

Currently, I am once again experimenting with the USB connection and AC config.

[Cornan]

Using optical ethernet makes perfect sence when using a NAS and playing DSD128 and higher. I would personally use it only for the NAS connection. If you like me are using Tidal as the only music source wifi is very good and beats normal wired network. I have a wireless extender for my control point (5G-EXT) and the remaining household is using 2,4 wireless. My Aries Mini is the only device using my routers direct 5G network. This makes a big difference!

BTW. Since my router is using a F-plug input I have used this Supra Aerial F-Con to galvanicly isolate the INPUT to the router as well. My Internet respond quicker and it sounds better as well.

 

Sent from my Nexus 7 using Computer Audiophile mobile app

[One and a half]

With so many small DC power supplies powering far too many components, the chances for ground loops are very high. I see a few USB connections between the Recovery and the Aries which gives me the shivers. Try and connect as many as possible from the one PSU and avoid mutliple power supplies wherever possible. Sadly, each manufacturer goes their own way and there's different voltages for everything...omg a real dog's breakfast.

 

Don't count on the PSAudio device to give you AC isolation and the AC will be the last place you get noise from. I would wait for the LPS-1 to arrive and incorporate it wholesale or figure out a less cable intensive system with less devices in the chain. For example, the Focusrite D16R system would be the way to go with the advantage of Ethernet to AES3 direct and then to the DAC, far simpler, and still streaming with isolation. Can still use the FO media converters, but use the same ones and T off the one unit.

[austinpop]

With so many small DC power supplies powering far too many components, the chances for ground loops are very high. I see a few USB connections between the Recovery and the Aries which gives me the shivers. Try and connect as many as possible from the one PSU and avoid mutliple power supplies wherever possible. Sadly, each manufacturer goes their own way and there's different voltages for everything...omg a real dog's breakfast.

@One and a half: you've articulated exactly why I created this thread. Every "fix" has a cost in complexity, additional PS, potential for ground loops. etc. You call it a dog's breakfast, I call it a minefield!

 

You say:

Try and connect as many as possible from the one PSU and avoid mutliple power supplies wherever possible.

That is what I was thinking, by adding an LPS with multiple taps like the HDPlex. But even that is a minefield. Some have advised against that, especially when it spans an isolation boundary. I am still awaiting a good explanation for that rationale.

 

Don't count on the PSAudio device to give you AC isolation and the AC will be the last place you get noise from. I would wait for the LPS-1 to arrive and incorporate it wholesale or figure out a less cable intensive system with less devices in the chain. For example, the Focusrite D16R system would be the way to go with the advantage of Ethernet to AES3 direct and then to the DAC, far simpler, and still streaming with isolation. Can still use the FO media converters, but use the same ones and T off the one unit.

 

I'm deterred by the cost of the LPS-1, but I agree it looks fantastic.

 

I sympathize with your advice to bypass USB and use AES, but sadly both the Aries Mini and the Codex don't support AES, and claim to work best with USB.

[Cornan]

This is not as complicated as it may look.

 

First step is to ensure that no power and unneccessary ground (GND & shielding/dielectrics) is in the signal path (incl. ethernet & XLR). No active galvanic Isolators in the path IMO.

 

Second step is to ensure good power supply...leaving just AC mains connected device in the audio chain. All DC connected devices should be changed to battery or ultracapacitors (ex. LPS-1) powered by battery that do not not send noices back into the mains (of course not connected to mains while listening to music).

 

Third step (but not least) is to ensure good grounding so the remaining noise have an easy path to ground.

 

Sent from my Nexus 7 using Computer Audiophile mobile app

[One and a half]

That is what I was thinking, by adding an LPS with multiple taps like the HDPlex. But even that is a minefield. Some have advised against that, especially when it spans an isolation boundary. I am still awaiting a good explanation for that rationale.

 

I'm deterred by the cost of the LPS-1, but I agree it looks fantastic.

 

I sympathize with your advice to bypass USB and use AES, but sadly both the Aries Mini and the Codex don't support AES, and claim to work best with USB.

 

Just a snip here and there to reduce the overload of the repair by breaking it down in parts.

 

The ideal is one large power supply to drive all devices. The reason for that is, the ground plane is the same. The resultant current from the AC is the sum of all secondaries, plus losses in the transformer stage. hold this though for a second. If you have different voltages from the same source, imagine a large DC supply, some 15Vdc 6A something and multiple regulator circuits for 12V, 9V, 6V etc. You still have the advantage of the same DC source, but the return ground planes will be different, since they will have different return currents. The end result is a mush of currents in the DC source. Hence the reason for creating the LPS-1. For the LPS-1, all supplies are isolated from each other, so you could still have a large DC source and a cavalcade of LPS-1 and complete isolation, yay!

 

High level harmonics reduction - Not tried yet for audio

You 'could' do something really special with the transformer's secondaries, so that each downstream power supply sees a secondary winding with a displacement. The displacement winding is offset from the primary by something other than 180 Degrees. It can be 30 or 60 degrees. The trick is to have another secondary winding displaced at the same angle but retarded, like -30 degrees to the +30 degrees. The net effect of any out of balance currents, especially the noisy shite, will 'dissolve' (as heat). This will only work if the load currents are the same. Given the loads may vary, and our voltages are different, such a transformer is an idea, but not a very practical one for small loads.

 

Other than battery supplies, or a wholesale LPS-1, the ground loops will still be there. So other than a technical solution, it becomes a commercial and philosophical decision also. Like most of us, we evolve our audio systems and keep on building and fixing things, until the number of tweaks get out of hand and cause us more problems than we can solve.

 

I've completed this recently this week, with removing USB as the transmission from audio. USB worked for a while, but there's always fiddling, and far too many devices and connections in the way, so had enough. Returned the RME AIO sound card to service and AES3 is sourced from the computer to the DAC, straight through 2 x MC-3+USB reclockers. PCM never sounded so good.

[r_w]

It's about time I did this, hope it helps anyone.

 

[r_w]

... This one is probably a bit easier to follow:

 

[austinpop]

Optimal would really to use a Vbus2 between the Aries Mini & Recovery AND between Recovery & Ayre Codec DAC. Even if Recovery will provide clean 5v power nothing beats no power at all since it blocks all the noise from entering via the 5v lead...not just make it cleaner. Aries Mini also gain a lot from blocking the 5v IME.

 

Well, I just received my Vbus2, and I tried connecting it between the Aries Mini and the Ayre Codex. No go.

 

Exact details:

 

Aries Mini -- Vbus2 -- Cardas Clear USB 2m -- Ayre Codex

 

The Sbooster site declares the Auralic Aries (but not the Mini) as compatible with the Vbus2. I have read the Ayre Codex does not require the 5V on input.

 

At this point, I will contact Ayre for clarification. I'll also try as many different cables I have on hand as well. Specifically, I'll try a shorter cable. I should have my Curious 0.2m "Regen link" within the next week or so.

[austinpop]

... This one is probably a bit easier to follow:

 

[ATTACH=CONFIG]29145[/ATTACH]

 

Thanks @r_w

 

Can you clarify a couple of things:

1. You show a link from the Swagman LPS to the Intona Industrial, but the Intona is not a powered device, so...?
   
2. What does the phrase "Data only : Gnd Switch" mean?
   

[Cornan]

Well, I just received my Vbus2, and I tried connecting it between the Aries Mini and the Ayre Codex. No go.

 

Exact details:

 

Aries Mini -- Vbus2 -- Cardas Clear USB 2m -- Ayre Codex

 

The Sbooster site declares the Auralic Aries (but not the Mini) as compatible with the Vbus2. I have read the Ayre Codex does not require the 5V on input.

 

At this point, I will contact Ayre for clarification. I'll also try as many different cables I have on hand as well. Specifically, I'll try a shorter cable. I should have my Curious 0.2m "Regen link" within the next week or so.

 

I can confirm 100% that Aries Mini is'nt the problem. I am using Vbus2 myself after Aries Mini and after Regen in my setup. First suspect is the DAC. It might need 5v for the handshake/hello. Good call to contact Ayre for a clarification.

 

Sent from my Nexus 7 using Computer Audiophile mobile app

[r_w]

Hi,

 

The Intona is powered but it usually uses the 5V USB power rail from the sender device.

 

I use a split USB cable to inject clean power into the Intona, so it's a data only cable from the Aurender fused with a power only cable from a Swagman LPS... after handshake, I have switches in all of the USB cables to cut the ground line, where I believe noise travels.

 

Thanks @r_w

 

Can you clarify a couple of things:

1. You show a link from the Swagman LPS to the Intona Industrial, but the Intona is not a powered device, so...?
   
2. What does the phrase "Data only : Gnd Switch" mean?
   

[austinpop]

Do you build your own split USB cable, or do you have a recommended one that I can buy?

 

 

Sent from my iPhone using Computer Audiophile

[r_w]

I make them myself... as short as possible.

 

Do you build your own split USB cable, or do you have a recommended one that I can buy?

 

 

Sent from my iPhone using Computer Audiophile