The iFi iUSB Power Supply - Neat Tweak & Upgrade for USB DAC

[Blake]

Addendum No.2 to my post directly above.

 

 

Yesterday, I finally got around to upgrading the OSX on my MacBook Pro from Snow Leopard to Mountain Lion. To repeat what I noted above, my MBP is a mid/late 2007 model, and I mentioned that I had not been able to run Audirvana in "Integer Mode" with my iUSB connected to a KingRex twin-headed (Y shape) USB cable, but otherwise, the twin-headed KingRex was working great.

 

The terrific news for me is that I have no idea why, but with Mountain Lion now installed, I can run Audirvana in "Integer Mode" with the KingRex twin-headed USB cable. So, as long as you are running Mountain Lion, the caveat in Paragraph 1 of my post above, no longer applies.

[Elberoth]

Anyone opened one already ? I wonder how it looks inside.

[AlainGr]

Anyone opened one already ? I wonder how it looks inside.

See post #274 of this thread

[wisnon]

Gemini cable to ship early March (along with their USB converter, most likely).

 

Taken from FBook

 

 

iFi Gemini Dual-Headed USB Cable - One cable to rule them all

 

London, U.K. – 8th February 2013

 

The Gemini Dual‐Headed USB cable is iFi’s approach to the highest quality of USB audio and power transmission. Available in March, the 2 lengths are: 1.5m (US$199 ex‐tax) and 0.5m (US$129 ex‐tax).

 

Features:

Dual‐headed (Gemini) connection USB design

Heavy OFHC copper conductors (up to 5A)

Custom PE insulation

Asymmetric Ground return and power line design

(3 times more ground area)*

Adjustable RF Filter to tune cable to environment*

Double shields with different effective range

Multiple RF filters*

 

*: iFi exclusive, world first.

[Sherwood]

So, as a quick intro, i'm an American audiophile living in Beijing for the next two years. im learning to adapt my inteests to the local market here, rather than just shipping everything from the U.S. back here (where it was likely made).

 

My interest in this cable got me thinking: "isn't this probably made in China? And, if so, doesn't that mean it's probably already available for cheaper here in China?"

 

Sure enough, it is. You can wait until March and pay $200, or you can get it now for $140.

 

http://item.taobao.com/item.htm?spm=a230r.1.10.1.v3m0mI&id=17237341403

 

If you don't read Chinese, you can use a Taobao brokerage service as a middleman -- adds $20 with shipping and commission.

 

Happy year of the snake!

[Sherwood]

You can wait until March and pay $200, or you can get it now for $140.

 

iFi audio Gemini Dual-Headed USB Cable Gemini

 

Correction: I missed a clause on the bottom -- looks like the pricing is the same here in China. Probably makes it a hassle to ship overseas to get it a few weeks early. On the other hand, mind should be here in Beijing shortly

[Blake]

You can wait until March and pay $200, or you can get it now for $140.

 

When did iFi announce the price of the Gemini cable? I was not aware official pricing info had been revealed.

[wisnon]

R U sure?

 

Chinese New Year over yet?

 

Dont think you will get it before the 26th of Feb...I'm just saying!

[wisnon]

When did iFi announce the price of the Gemini cable? I was not aware official pricing info had been revealed.

See my post above, taken from their Facebook page....posted last saturday.

[Blake]

See my post above, taken from their Facebook page....posted last saturday.

 

Thanks.

[Sherwood]

Chinese New Year over yet?

 

Chinese New Year (or Spring Festival) officially ended today, yes. The traffic jam headed back into Beijing last night certainly attests to that

 

Of course, factories with far-flung workers will remain closed until the 25th, so I see why iFi has to wait until after then for their full order. Nevertheless, in the meantime half of the small stock on Taobao has sold out, and they're actively shipping. I hope to put up pictures soon!

[wisnon]

OK thanx Sherwood.

 

Godspeed on the cables then.

[Emcee]

So, as a quick intro, i'm an American audiophile living in Beijing for the next two years. im learning to adapt my inteests to the local market here, rather than just shipping everything from the U.S. back here (where it was likely made).

 

My interest in this cable got me thinking: "isn't this probably made in China? And, if so, doesn't that mean it's probably already available for cheaper here in China?"

 

Sure enough, it is. You can wait until March and pay $200, or you can get it now for $140.

 

iFi audio Gemini Dual-Headed USB Cable Gemini

 

If you don't read Chinese, you can use a Taobao brokerage service as a middleman -- adds $20 with shipping and commission.

 

Happy year of the snake!

 

Can you please explain how I can order one - I don't see any ordering info in English.

 

Thanks

[wisnon]

Wait 2 weeks and they will be available in the US. No need for the big hassle to get from China.

[Sherwood]

Can you please explain how I can order one - I don't see any ordering info in English.

 

Yeah, unfortunately there is no English on taobao, and it's difficult to use anything but a Chinese bank account to pay. You are far better off following Wisnon's wise advice and waiting for the cables to be available internationally.

 

For all the trouble you would go to setting up an account, translating Chinese for ordering, and enlisting a broker, you may well not even receive the product before it's released locally.

 

I more posted it for fun, and to express my growing amazement at the incredible web service that is Taobao.com

[obt_man]

Does anyone know if iUSB is still worth using if DAC doesn't draw 5v power from the USB port? The DAC I own does not use any PC power for its USB receiver, so I am not very confident that I will use iUSB to its full potential. Please advise.

[squidly]

Does anyone know if iUSB is still worth using if DAC doesn't draw 5v power from the USB port? The DAC I own does not use any PC power for its USB receiver, so I am not very confident that I will use iUSB to its full potential. Please advise.

I can't remember which review I was reading, but the consensus was that it wasn't nearly as effective on DAC's that draw power from the USB bus.

[gtener]

Has anyone tried the iUSB with an Audiophilleo 2?

[One and a half]

A good sign a tweak or a new piece of equipment installed that makes an average recording sound better, and a great recording outstanding, is a tweak worth the effort.

 

After a few hours listening to the ifi iUSB in my system using a Nordost Blue Heavan cable for input and output to the iUSB, switching back and forth revealed the 'without' to be kinder on the ears and not as hard, as if the decoding went a bit off the rails. Adele's 21 in a few moments is not a 'bad' recording, but overly compressed anyway, the iUSB made it worse.

 

For Dave Brubeck's 176/24 Time Out has marvellous top hat/cymbals, with just nice decay for an old 1959 (!) recording, it's really well done, here with the iUSB, the results are splashy and no decay. Didn't bother with assessing the soundstage, the tonal quality just missed the mark.

Several times, I had to stop the music, it's not pleasant, there's something really wrong. Well, can't do much with the connections, in and out and the PSU, they are all good, nothing else to tweak. I did consider break in, but is it going to get better, 'that' much better? Even out of the box, there should be something better, not worse.

 

The earthing switch made no difference and this could be the clue. If the earth (the USB shell) is clean to begin with, then there's nothing for the iUSB to perform, it just adds another wire length, adding capacitance with the cabling. The Gemini would then have limited value, possible worse, by adding more cable capacitance.

 

If on the other hand, your earth is not clean, like for TN systems where the earth is connected to neutral, then the iUSB would benefit since the earth contains all manner of evils, but for balanced AC power or those who have squeaky clean mains power, it's far from necessary to have the iUSB.

 

Johnathan Timm was right after all, hats off to you.

[One and a half]

Has anyone tried the iUSB with an Audiophilleo 2?

 

Give me a week or so..

[knickerhawk]

 

The earthing switch made no difference and this could be the clue. If the earth (the USB shell) is clean to begin with, then there's nothing for the iUSB to perform, it just adds another wire length, adding capacitance with the cabling. The Gemini would then have limited value, possible worse, by adding more cable capacitance.

 

If on the other hand, your earth is not clean, like for TN systems where the earth is connected to neutral, then the iUSB would benefit since the earth contains all manner of evils, but for balanced AC power or those who have squeaky clean mains power, it's far from necessary to have the iUSB.

 

Johnathan Timm was right after all, hats off to you.

 

In my setup (Synology 213+ NAS running the Synology Audio Station server > iUSB > Emotiva XDA-2 dac > Emotiva XPA 200 amp) the iUSB makes a quite noticeable improvement on pretty much all tracks and all sampling rates. Without the iUSB the XDA-2 sounds a little lean and "digital". With the iUSB, the setup sounds fuller, less edgy but with no apparent loss of detail. For me the acid test is whether on bad recordings I'm tempted to turn down the volume. I'm much more inclined to do that without the iUSB inline than with it inline. Your grounding theory doesn't seem applicable to my setup either. Switching the ground setting back and forth doesn't make any difference that I can detect. I run my system in balanced mode and its dead quiet with or without the iUSB inline.

 

For me, the bottom line is that this is one of those tweaks that's very hard to predict the effect. In my case, the $200 was well worth it, but definitely a YMMV situation. (By the way, it also improved my Audioquest Dragonfly setup).

[ted_b]

A good sign a tweak or a new piece of equipment installed that makes an average recording sound better, and a great recording outstanding, is a tweak worth the effort.

 

After a few hours listening to the ifi iUSB in my system using a Nordost Blue Heavan cable for input and output to the iUSB, switching back and forth revealed the 'without' to be kinder on the ears and not as hard, as if the decoding went a bit off the rails. Adele's 21 in a few moments is not a 'bad' recording, but overly compressed anyway, the iUSB made it worse.

 

For Dave Brubeck's 176/24 Time Out has marvellous top hat/cymbals, with just nice decay for an old 1959 (!) recording, it's really well done, here with the iUSB, the results are splashy and no decay. Didn't bother with assessing the soundstage, the tonal quality just missed the mark.

Several times, I had to stop the music, it's not pleasant, there's something really wrong. Well, can't do much with the connections, in and out and the PSU, they are all good, nothing else to tweak. I did consider break in, but is it going to get better, 'that' much better? Even out of the box, there should be something better, not worse.

 

The earthing switch made no difference and this could be the clue. If the earth (the USB shell) is clean to begin with, then there's nothing for the iUSB to perform, it just adds another wire length, adding capacitance with the cabling. The Gemini would then have limited value, possible worse, by adding more cable capacitance.

 

If on the other hand, your earth is not clean, like for TN systems where the earth is connected to neutral, then the iUSB would benefit since the earth contains all manner of evils, but for balanced AC power or those who have squeaky clean mains power, it's far from necessary to have the iUSB.

 

Johnathan Timm was right after all, hats off to you.

 

I think, your generalities aside, that all you have proven is that the iUSB does not improve PD MPD-3 playback. Maybe that DAC doesn't use computer 5V power, dunno. But to generalize and say it's purely an earth grounding issue is wrong, IMO. My Meitner's grounding issues are moot (earth switching made no diff, and I have very clean power into the dedicated music room), yet the added cleanliness of the 5V iUSB (and dual conduit when demo'd) vs the mobo-induced power is night and day.

[wisnon]

One and a hlf....this is taken from posts 82 to 84 on this very thread:

 

1. Why a USB Power Supply?

 

by iFi Audio on Thursday, November 1, 2012 at 11:43am •

We get asked this a lot. Why would anyone need this Box?

It is simple. USB carries audio AND power. Many USB Audio devices power at least some part, often all of the Audio Device from the power supplied by the Computer via its USB Port. The power supply from USB Ports on PC’s is variable in quality, but always contaminated by noise. Have a look here comparing the noise from the best (lowest noise) USB Port on a PC optimised for audio idling… When playing music this is worse.

This is a lot of noise! Many common Laptops and PC’s put out tens of millivolts of noise. That is as much noise as you often get music signal and much more noise than the delicate, small details and nuances in a musical performance. Another issue is the presence of a ground connection between the Computer and the USB Audio device. This can create earth/ground loops that even if they produce no audible hum or buzz, sound quality can be impaired.

So it is little surprise that computer based audio often fails to live up to the expected and possible excellent sound quality.So why do manufacturers keep relying on USB Bus Power? Cost plays a role, as does portability and practical considerations.

Adding the iUSBPower USB Power supply and breaking the ground loop using the IsoEarth gives a major improvement in clarity, detail and musicality. Any audio device starts with the power it receives and with the iUSBPower USB Power supply your USB Audio device gets power so pure, it has even lower noise than a battery!

But the true secret weapon is the ability to break ground loops. We have measured an improvement of over 10 times even in system that are already optimised and have no audible noise.

Like • • Share

 

>>>>This is a Critical part of ANY highend USB based music server!

November 4 at 4:38pm • Like • 1

 

>>>>> is the power supply galvanic isolated, pardon my ignorance.

November 6 at 10:01am • Like

 

iFi Audio Not sure in which way you mean this? In order to keep compatibility with high speed USB2 (480MBps) to allow multi-channel use at high sample rates/resolution we cannot employ USB isolators. All current isolators are limited to 12MBPS or 2 Channels at 96KHz, which we felt was not acceptable for modern audio. So we cannot fully, galvanically isolate the DAC and PC.

 

However, full isolation is not strictly needed. USB Signalling is differential, so in theory only the two signal lines are required. In practice we need somehow a ground reference. If this ground reference comes only through the USB cable, all is well.

 

If there additional path through other equipment and mains wiring things become problematic.

 

So our "IsoEarth" feature allows breaking the ground connection in a way that is reliably safe for attached equipment (sorry to be vague, but we consider the precise method a "trade secret") and does not require "earth lift" or "cheater" plugs.

 

As we also interrupt the power line from the computer and substitute our own super regulated very low noise supply from the Computers power we essentially only leave the two USB signal lines active and connecting between PC and DAC is IsoEarth is engaged.

 

I have measured differences in of around ten times (20dB) with IsoEarth engaged in systems we use for testing - that is they are already quite well treated regarding the ground noise problem!

 

When testing a USB Isolator marketed for Audio in the same setup I observed similar gains in ground noise levels as with the iUSBPower, suggesting that in our system at least breaking the ground line and full isolation perform comparable, objectively. I did observe that the 5V output from the USB Isolator was quite noisy due the use of an isolating DC-DC converter, which basically a small switched mode supply.

 

Sorry for the lengthy missive, but it is not a simple subject.

November 6 at 10:29am • Like

 

>>>>> how does this device actually work? I am not sure how it is to be used. It is not a USB-Spdif converter, so what actually is it? How would it be used with such a converter? Is the iUSB powered by a SMPS?

Wednesday at 12:20am • Edited • Like

 

>>>>> Is there a manual online?

Wednesday at 12:17am • Like

 

iFi Audio ,

 

First, you can find more details and manuals etc. On-Line.

 

Secondly,the iUSBPower plugs into the USB connection between the PC/Mac and any USB Audio Device. Some of the more extreme High End gear does not draw power from the USB, the vast majority of USB Audio Devices, including USB to SPDIF Converters do.

 

In recent times we have seen some attempts to for example split up USB Cables and Lithium Polymer batteries to substitute the power supply, however most batteries when actually supplying are quite noisy (see our AP2 measurement which includes a 9V Dry Cell, rechargables are worse).

 

The iUSBPower contains noise filtering using multiple LCR filters and a so-called super regulator (as opposed to a simple cheap 3-pin regulator) which is similar but not identical to the one described by Walt Jung under this name.

 

As a result you isolate the USB Audio Device (including USB to SPDIF converters) from the computers power supply and you give a power supply much cleaner than that from the Computer.

 

Additionally we have also build in some ground impedance management and the option to break the USB ground connection entirely. This can help a lot with noise loops.

 

Third, you ask is it powered by an SMPS, plugtop type which we supply, however any source of around 9V DC may be applied (at your own risk, mind you). As we wanted a simple way of being able to sell and use the iFi worldwide and we wanted to avoid wasting power, we had to use a custom low noise SMPS.

 

In basic principle an SMPS is a much better choice power supply than using 50/60Hz rectified. The high frequency at which they produce their AC means transformers can be small and thus minimise noise leakage from the mains, they always use choke input filtering and the high frequency means relatively small components are required to filter any noise.

 

Another factor, such a supply may be made universal (runs on any mains voltage/frequency current, even DC) and if well designed efficiency will be very high, well over 90%.

 

However, many common inexpensive examples are build so badly they barely pass FCC requirements. This means they radiate a lot of noise back into the mains and often have very large levels of noise on the output.

 

The first examples we bought straight in shops like Radio-shack were horrendous. The noise on both the mains input side and the output side was sufficiently high to be visible easily on cheap oscilloscopes. output ripple went from 10's to 100's of millivolt.

 

Opening them up revealed that the RF filtering was not fitted, that the chokes and capacitors where of insufficient value and that several parts that would have produced low noise where missing, even though there where spaces provisioned on the PCB to fit them.

 

So we worked with a factory to produce our own plug-top power supply, which not only has all the extra parts fitted but goes beyond this. The result is a power supply that leaks very little noise into the mains (you can measure it, but it needs an expensive analyser, scope traces are clean).

 

Overall, a common linear supply using a transformer, common rectifiers and a 3-Pin regulator will produce more noise (including noise radiated into the mains) than our SMPS. Do not expect most SMPS's to perform similarly.

 

Finally, why don't you just try it? Ask our US distributor for a loan unit.

Wednesday at 4:43am • Like

 

>>>>> Thanks for the detailed and thorough explanation. I can now see more clearly the benefits and I do agree that a properly made SMPS is actually an advantage.

Yesterday at 7:33am • Edited • Like

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In an email from Vincent Luke of AMR Re: IsoEarth on iUSB

Alex,

 

Thorsten and I had a good chat today and this is the following of what came out. We also sent this to AudioStream.

 

IsoEarth 2 pins or 3?

 

“IsoEarth" works by breaking earth/ground loops that can occur in and around the computer itself or other items in the system (e.g. USB Hard Drives). This can lead to audible hum or buzz or if it is not audible, may degrade sound quality.

 

As the power supply of most MacBooks do not have an Earth Connection on the power supply this particular feature will not provide any benefit as such (the earth connection giveaway is if the 'power brick' has 2 or 3-pins). Desktops being of the 3-pin variety are almost all certainly earthed.

 

Interestingly from tests conducted, even a computer with no earth can benefit if the external HDD connected to it is earthed. We came across one such instance where a WD USB MyBook (earthed) connected to a MacBook (not earthed) with the addition of the iUSB removed severe levels of hum."

 

 

And, why "IsoEarth" may not work for some?... as in my case.... …if your ground is lifted, there is nothing for IsoEarth to lift!

No more... no less complicated than that

[DM]

My friends and I have tried the iUSB Power with over 8 DACs, including dCS, Weiss, wyred4sound, EmmLabs, Mytek, M2Tech, AMR, Asus etc. This little thing brought significant improvement to all of them.

 

At first we were all pretty amazed about the improvements, but now if one of my friends rang me up and say, "Hey, have you try the iUSB Power? it really improved my DAC.", I will reply "come on, this is such old news ..." :-)

 

The iUSB Power basically improve improve the original characteristic of the DAC by 10-30%, so far none of the DACs sounded worst after the iUSB, all sounded significantly better, smoother, more body, more details.

 

In one case, the iUSB initially didn't improved much, we hence were a bit puzzled. after some investigation, the Crystal Dreamline USB Cable was the culprit. Once we have removed this cable from the system (w/o the iUSB yet), his system actually performed better in teams of details and resolutions, but the sound became more "digital" too. Then we added the iUSB Power, it kept all the improved details and resolutions and remove the "digitalness".

 

The Crystal Dreamline USB Cable was actually hiding the flaws in his system (too digital sounding), but by doing so, sacrificed details and resolution.

 

On the other hand, iUSB power remove the flaw altogether and able to kept details and resolution. At the end of the day, this little wonder is a bargain IMHO ... YMMV

[One and a half]

I think, your generalities aside, that all you have proven is that the iUSB does not improve PD MPD-3 playback. Maybe that DAC doesn't use computer 5V power, dunno. But to generalize and say it's purely an earth grounding issue is wrong, IMO. My Meitner's grounding issues are moot (earth switching made no diff, and I have very clean power into the dedicated music room), yet the added cleanliness of the 5V iUSB (and dual conduit when demo'd) vs the mobo-induced power is night and day.

 

The clean 5V from the iUSB is used the PD designs as acknowledgement that there is a computer connected, and please standby for the signal, like the cavalry, will arrive shortly. That's the extent of the 5V rail, so it's not used to drive a differential pair or to make a new reference, nothing like that. The easiest way to do this is with an opto, done.

 

Ted, we differ (again) on the grounding issue this time. Introduced noise especially from the computer, or noise coupled at the receiver is the primary target for the iUSB to isolate. AND for a TN earthing system, that applies, the iUSB does a good job of that. You can have a clean supply to the Meitner, but have you measured how clean it really is, unless you run balanced AC, your earth will still carry noise and devices like the iUSB can clean this situation up, so in other words, the iUSB is a band aid, and not the cure. It is entirely possible that the music server is emitting conducted noise, which the iUSB can clean up, night and day.

 

As our fellow CA member Flac2Dac discovered the bad hum and noise present in his new caps system was due to a floating PSU causing noise to channel from the PC to the DAC and audibly to annoy.

 

So, I rather find the root cause of the noise problem rather than apply the band aid.