Group Test: USB gadgets (AQ Jitterbug, Uptone Regen, iFi iUSB3.0, iPurifier, iPurifier2, UPDATE on p.15…)

[mmerrill99]

Yes, some DACs function with USB cables, where VBUS is broken.

Although it is nonstandard USB implementation, in the case of DACs it is seen rather an advantage.

 

Yep, I agree - it can be beneficial to the sound. Why? Probably got to do with the nature of the signals that are being carried in the USB cable.

 

BTW, I find it hilarious that what Plissken would define as "competently designed" USB DACs (because he thinks having no 5V Vbus makes them "beyond USB improvement") includes these nonstandard USB implementations. Just shows how lost he is - chasing his tail around in ever decreasing circles - where his definition of "competent" now means breaking the standards, lol.

[DM]

Hi,

 

we have had to await confirmation from another dept but we are now very pleased to confirm the global launch date of mid-April. It will be the very first and only audiophile-grade galvanic isolation device on USB3.0. There is a very good reason why it will be the only one....because galvanic isolation on USB2.0 alone is problematic but we are pleased as punch that our Skunkworks has managed to solve this issue and on USB3.0 too. We will update the features as soon as we can.

 

 

We're excited!

 

 

 

[ATTACH=CONFIG]33629[/ATTACH]

 

Please tell!!!!!!!!! all-in-one Isolation on USB3.0, you are not kidding?

[comedus06]

Has anyone tried this product? Waversa audiophile grade switch and USB hub - claims to filter electric noise and reclock USB in one box; battery powered. Any opinions or listening impressions?

 

Waversa Smart Hub — Waversa North America

[kilroy]

The problem with the listening reports & comparisons of these devices is disentangling the 5V power supply improvement from the improvement wrought by isolation & regeneration/reclocking.

I'm not exactly sure what DAC these devices are being tested with but it seems to require 5V Vbus input. It would be good to also use a DAC which is self powered to evaluate the isolation/reclocking aspect of these devices

 

My Auralic Vega is used for listening impressions. Does not use 5V.

[mmerrill99]

My Auralic Vega is used for listening impressions. Does not use 5V.

Yea, thanks but not sure this is the case with DM's setup - his seems to need 5v & he's the one doing the tests & comparisons.

 

All I'm saying is that the influence of the 5v on sound quality needs to be disentangled from the influence of the isolation & rocking aspects in order to be able to judge comparative performance.

[DM]

Yea, thanks but not sure this is the case with DM's setup - his seems to need 5v & he's the one doing the tests & comparisons.

 

All I'm saying is that the influence of the 5v on sound quality needs to be disentangled from the influence of the isolation & rocking aspects in order to be able to judge comparative performance.

 

I have both. The DP-777 doesn't use USB 5V, but most of my portable USB DACs did use the USB 5V.

 

For all the USB DACs out there, may be >90% will use USB 5V, so "USB Power" is one of the main factors and can't be ignored in real life.

[ElviaCaprice]

Yea, thanks but not sure this is the case with DM's setup - his seems to need 5v & he's the one doing the tests & comparisons.

 

All I'm saying is that the influence of the 5v on sound quality needs to be disentangled from the influence of the isolation & rocking aspects in order to be able to judge comparative performance.

 

I think this is a very good point. The influence of the 5Vbus and whether it is being fed to the DAC dirty, clean (what source do you consider clean?), or not at all is an important factor to distinguish and may influence results. My point exactly about the Intona or Regan. Feeding them a clean 5Vbus transforms them into a whole new device. The fact that they can receive a clean power source can be a positive factor in versatility to other devices claiming similar abilities without power source versatility.

 

Thus we are back to system integration and versatility with the following being of great importance. Power, isolation, components. Any changes to those three main factors can change the outcome of the testing for each specific component.

[DAW1d]

Hello, thank you very much for review. I am dealing with USB noise for few months and this is very helpfull. I want to go with iPurifier but I think I will go for iUSB 3.0. Also do you have experience with products from Elfidelity? They are making lots of product with similar purpose:

 

Music Hall Elfidelity USB Power Source

 

Music Hall Elfidelity USB Boosters USB-audio interface

 

Music Hall Elfidelity PC HI-FI Power Filter card PCI/PCI-E

 

Music Hall Elfidelity 4 Pin FAN Power Noise Filter

[monteverdi]

One thought about optical USB connections. The Corning implementation has still an electric ground/5V connection and is therefore not fully isolating electric noise. What if one would design a fiberoptic system in which the sender is powered by the sending device (USB) and the receiver by a separate power supply so that there is only an optical connection. The receiver could also incorporate a reclocker etc.

Does anything like that exist?

P.S.: It would even not need an optical cable but optical coupler like AquaHifi has in its newest DACs.

[mmerrill99]

I have both. The DP-777 doesn't use USB 5V, but most of my portable USB DACs did use the USB 5V.

Ok, thanks

For all the USB DACs out there, may be >90% will use USB 5V, so "USB Power" is one of the main factors and can't be ignored in real life.

Really, I'm not sure about that >90%?

Here's something to think about - is a USB DAC that uses Vbus as it's power source a good design choice for optimal sound? Great for portability but not so much for great sound. If the objective of these USB gadgets is best sound then maybe using USB DACs which are powered by Vbus is not a wise choice?

[r_w]

After handshake the VEGA doesn't need the GND either. It's a class act with just the 2 USB data wires connected.

 

 

My Auralic Vega is used for listening impressions. Does not use 5V.

[ElviaCaprice]

Ok, thanks

Really, I'm not sure about that >90%?

Here's something to think about - is a USB DAC that uses Vbus as it's power source a good design choice for optimal sound? Great for portability but not so much for great sound. If the objective of these USB gadgets is best sound then maybe using USB DACs which are powered by Vbus is not a wise choice?

I would have agreed, before hand, about the preference for not powering a DAC via the Vbus, but I have to admit that I am quite impressed, if not surprised, with the quality of sound from the ifi nano idsd LE by powering it by the Vbus. It's definitely better than the battery, although I use a LPS-1 via Regen to power the ifi. In fact, one could make the argument that it may be better to have a DAC that is powered via the USB Vbus, for it would be easy then to power with the galvanic isolated supply Uptone LPS-1.

What could be lost in SQ because of the proximity of the clean 5Vbus to the data? I still break the 5Vbus, by eliminating it in the USB cable between the Intona and Regen. It does trump the battery supply only power.

[mmerrill99]

I would have agreed, before hand, about the preference for not powering a DAC via the Vbus, but I have to admit that I am quite impressed, if not surprised, with the quality of sound from the ifi nano idsd LE by powering it by the Vbus. It's definitely better than the battery, although I use a LPS-1 via Regen to power the ifi.

I'm not sure I follow - Vbus powering iFi nano is better than what battery power?

In fact, one could make the argument that it may be better to have a DAC that is powered via the USB Vbus, for it would be easy then to power with the galvanic isolated supply Uptone LPS-1.

Again, I don't get this - feeding a cleaner supply into where Vbus once ran is not the best design choice - poor wiring, poor connections, non-optimal routing, etc.

What could be lost in SQ because of the proximity of the clean 5Vbus to the data? I still break the 5Vbus, by eliminating it in the USB cable between the Intona and Regen.

Yes, running a VBus wire alongside a twisted differential signal pair IMO, is not a good design choice from a the signal integrity viewpoint - ripple noise on vbus will not couple into both members of the differential pair equally hence common mode noise rejection will not be as effective.

It does trump the battery supply only power.

What battery supply?

[ElviaCaprice]

Yes, running a VBus wire alongside a twisted differential signal pair IMO, is not a good design choice from a the signal integrity viewpoint - ripple noise on vbus will not couple into both members of the differential pair equally hence common mode noise rejection will not be as effective. What battery supply?

 

The battery supply built into the ifi. Can run on battery or 5Vbus only. Not saying the battery supply design is optimum on the ifi??? But the 5Vbus power via LPS-1 provides better SQ than the battery supply only on the ifi.

I agree, the design choice of power supply via 5Vbus, we would think would not be of optimum choice, but I gotta say, on the ifi at least, it works very well.

[mmerrill99]

The battery supply built into the ifi. Can run on battery or 5Vbus only. Not saying the battery supply design is optimum on the ifi??? But the 5Vbus power via LPS-1 provides better SQ than the battery supply only on the ifi.

Right, battery in the iFi is not as good as supercapacitor power supplied via LPS-1. I find it confusing to call this 5Vbus as it has no relation to VBus, only uses the same wiring?

I agree, the design choice of power supply via 5Vbus, we would think would not be of optimum choice, but I gotta say, on the ifi at least, it works very well.

Sure!

[ElviaCaprice]

Right, battery in the iFi is not as good as supercapacitor power supplied via LPS-1. I find it confusing to call this 5Vbus as it has no relation to VBus, only uses the same wiring?

5Vbus and VBus are one and the same. I just like to distinguish that you have the spec USB 2.0 5V as power for the VBus.

I suspect that the effect of the Vbus 5V power has a negative effect on SQ in the ifi when operating under battery power, presumable it is still trickle charging the battery. Really to test properly the battery of the ifi as opposed to the LPS-1/Regen/Vbus power, one would have to cut off the Vbus so as to not influence the sound when being powered by the battery. Then the difference wouldn't probably be so much. But what a pain in the ass to have to do every time you want to use the DAC in desktop application.

[mmerrill99]

5Vbus and VBus are one and the same. I just like to distinguish that you have the spec USB 2.0 5V as power for the VBus.

Hold on - the way I thought you were using the term 5Vbus was to describe how power was being delivered from the LPS-1 along the Vbus wire or Vbus pin in the USB plug. This is very different to the VBus power that comes from a normal USB socket. This is all I meant & why I found it confusing a term.

 

But maybe you are using it as a term to describe the cleaned up VBus that is done inside the iFi - I'm not sure - I haven'tlooked into the iFi nano?

I suspect that the effect of the Vbus 5V power has a negative effect on SQ in the ifi when operating under battery power, presumable it is still trickle charging the battery. Really to test properly the battery of the ifi as opposed to the LPS-1/Regen/Vbus power, one would have to cut off the Vbus so as to not influence the sound when being powered by the battery. Then the difference wouldn't probably be so much. But what a pain in the ass to have to do every time you want to use the DAC in desktop application.

[misterspense]

Hello, thank you very much for review. I am dealing with USB noise for few months and this is very helpfull. I want to go with iPurifier but I think I will go for iUSB 3.0. Also do you have experience with products from Elfidelity? They are making lots of product with similar purpose:

 

Music Hall Elfidelity USB Power Source

 

Music Hall Elfidelity USB Boosters USB-audio interface

 

Music Hall Elfidelity PC HI-FI Power Filter card PCI/PCI-E

 

Music Hall Elfidelity 4 Pin FAN Power Noise Filter

How do you know you are dealing with USB noise? Because if you really hear noise through your speakers, I think the issue is more about grounding, or at least mor severe than what these devices try to do. With or without my Regen or Audio GD usb-spdif, I can hear clear differences in stage, clarity all the hifi stuff. But I never hear noise.

Isn't the USB noise we're talking about the digititus that you can visualise in eye-patterns, or in jitter measurements, and what is causing loss of audiophile pleasure?

 

 

Sent from my MI 2 using Computer Audiophile mobile app

[DAW1d]

I had ifi iDSD Nano and now with Audio GD NFB11 I hear almost the same noise in my studio monitors (JBL LSR 305). When I had ifi I tried iUSB 3.0 and the noise almost disapeared and iUSB havent any ground isolation. So that is the reason why I think it is some noise form PC (maybe PSU). I was trying to find solution in this thread if you want to check it. Now I am using NFB11 via toslink so it is ok, but bad thing is that sometimes I hear crackling sound. But even on AudioGD web there is info that toslink and coax isnt good interface for NFB11 and it is recommended to use USB. So that is the reason I will buy some USB "cleaner". I think iUSB 3.0 with iDefender will resolve my problem for good.

 

EDIT.: Ok so I am confused once more. I realized I didnt test NFB11 connected via USB with headphones (ifi was silent with headphones, no noise). But NFB11 has switch to select output and when I select headphone output the noise from speakers disappear and headphones are silent too. So I really dont know from what source is the noise coming and where is it going when I am using headphones

[bogi]

@DAW1d: Your trouble doesn't seem to be about USB noise. If it would be then you would hear it through headphones too. Look for a solution to avoid ground loop - probably between your speaker amplifier on some other audio component. That's other topic than this thread is discussing.

[mmerrill99]

@DAW1d: Your trouble doesn't seem to be about USB noise. If it would be then you would hear it through headphones too. Look for a solution to avoid ground loop - probably between your speaker amplifier on some other audio component. That's other topic than this thread is discussing.

I would disagree, Daw1d's issue would appear to me to be ground related - his headphones have no connection to mains ground whereas his amplifier/speakers would have. I suspect that it is leakage current noise that he is perceiving.

[blue2]

@DAW1d: Your trouble doesn't seem to be about USB noise. If it would be then you would hear it through headphones too. Look for a solution to avoid ground loop - probably between your speaker amplifier on some other audio component. That's other topic than this thread is discussing.

Try pulling out amplifier inputs except the DAC one by one until the noise disappears. Then try removing USB from the DAC and you'll know if the PC is causing the noise.

[DM]

A while ago I said a Chinese Blogger posted something regarding SMPS vs LPS testing, before I can repost/translate, he took it down. Now it’s back up again:

 

Part 1

Part 2

 

All in Chinese, but I asked the author for the permission to translate into English and the translation is posted here:

 

Power Supply (8+) Group Test, LPS and SMPS

[semente]

I agree - if you are presenting data as a means of comparison between devices then that data needs to be as accurate as possible.

 

Don't agree. What you hear & evaluate is the judge. Yes we can be swayed by bias & pre-disposition, just as easily as we can be swayed by measurement bias & pre-disposition. We are not talking about 'technical' quality as this becomes a meaningless term when we don't know what measurements equate to good sound.

 

So we have to live with the fact that we are using our auditory processing mechanism for judgement & evaluation of what we here in the knowledge that it is imprecise & flawed but we really don't have any choice!

 

Evaluating sound performance through listening requires effective methodology and adequate music.

Otherwise you're just "tasting" which is what a lot of audiophiles and reviewers do.

 

R

[mmerrill99]

Evaluating sound performance through listening requires effective methodology and adequate music.

Otherwise you're just "tasting" which is what a lot of audiophiles and reviewers do.

 

R

 

Funny but I judge food & meals in exactly this way - by tasting & am not interested in the chemical makeup of the food - it tells me nothing about how it will taste to me. I'm not interested in an "effective methodology" as it takes the life & fun out of what should be a pleasurable & enjoyable pastime.

 

Does my mood & the company & chat during a meal influence my judgement? Sure it does. If I go to the same restaurant many times with different people & in different moods does this lead me to a general idea of whether I like the food or not.

 

I find this works with many choices that I make. Can I get it wrong? Sure, but it's life & I try to enjoy the rollercoaster ride.