A Collection of USB Audio Enhancement Products

iFi iPurifier
Device Type: USB Filter
Input: USB (Type B)
Output: USB (Type B)
Dimensions (L x W x H): 62 x 19 x 18mm
Weight: 32g (0.0705 lbs)
Price: $99.00
Availability: through Authorized Dealers
Website: www.ifi-audio.com

Ultra Fi Aubisque USB Filter
Device Type: USB Filter
Input: USB (Type B)
Output: USB (Type B)
Dimensions (L x W x H): 58 x 14 x 12mm
Weight: 9.07g (0.02 lbs)
Price: $200.00
Availability: Direct Sales
Website: www.ultrafi.biz

Schiit Wyrd USB Decrapifier
Device Type: USB Power Isolator
Input: USB (Type B)
Output: USB (Type A)
Dimensions (L x D x H): 5 x 3.5 x 1.25 inches
Weight: 1.0 pound
Price: $99.00
Availability: Direct Sales
Website: www.schiit.com

Other components used in the review:
iFi Micro USB Power $199.00
iFi Mercury USB Cable .5 meter $99.00
iFi Gemini USB Cable 1.5 meter $249.00

Introduction
The 3 products under review all deal with common issues encountered in USB computer audio. Most USB DACs require a 5 volt line (VBUS) in the USB cable to supply power to the USB controller in one’s DAC. Unfortunately, this power line from the computer brings with it noise that can contaminate the audio data leading to degradation of the sound one hears from the DAC. The idea behind the Schiit Wyrd USB Decrapifier is that supplying clean power to your USB DAC, or better-quality USB port power management, can result in improvements in sound and performance. Schiit believes that glitches and dropouts can be prevented using the Wyred USB Decrapifier.

Another issue one faces in using USB audio is EMF noise from the computer. The EMF noise can also serve as another source of contamination of the audio signal and have a negative effect on the music heard from one’s DAC. The iPurifier and Ultra Fi Aubisque are filters that deal with this issue by inserting themselves between the USB cable and the DAC to filter EMF noise. In addition, the Aubisque has additional ground filtering.

Michael Lavorgna did a wonderful job reviewing the iFi Audio Micro USB Power for AudioStream. I decided not to repeat the work Michael has done, but instead, offer a sonic comparison of the Schiit Wyrd USB Decrapifier with the iFi Micro USB Power.

As I started work on this review project, I quickly realized that results could vary with the DAC and computer used. The strategy a DAC manufacturer uses for isolating the audio circuitry from USB computer noise varies with each audio designer. Some of the isolation techniques are quite involved. Interesting enough, some of the DAC manufacturers asked me not to release the specifics of their isolation designs. I also found that different USB cables can influence how these products work further complicating the issue. A third issue is that the computer used and its USB port management can influence the performance of the USB cable / DAC interface.

In this evaluation I used my early 2011 MacBook Pro running OSX Mavericks and Boot Camp Windows 8.1 Pro 64. The USB cables employed were the Audioquest Diamond, the iFi Mercury, iFi Gemini, and the Synergistic Research Galileo LE USB cables. The DAC used for my listening evaluation was the MSB Technology Analog DAC with Analog Power Base.

The Schiit Wyrd USB Decrapifier
Schiit states that the Wyrd USB Decrapifier eliminates noise and glitches caused by “crappy” USB power. The Wyrd can be used with any USB DAC as it supports all USB audio standards and up to 32/384. Above and beyond that, Schiit makes no claims as to the amount of noise reduction you will get or the sonic benefits, if any, to be obtained with its use.

Technical Description from Schiit

“Wyrd does two things: it replaces the noisy USB power from your computer with a low-noise linear power supply (no switchers here!) with precision regulators rated at 2.5uV RMS noise. This is literally 100,000X better than some of the USB ports we’ve measured, which have up to 500mv of hi-frequency noise. It also uses a tightly spec’d crystal oscillator on its own filtered power supply for the USB repeater chip for best possible stability.”
The Wyrd can supply over 500mA and consumes 6W maximum; less than 1W typical. An AC power 9VA 6VAC wall-wart is supplied with the Wyrd.

The Wyrd has an attractive aluminum case with two power indicators and a power switch. One light indicates that the power is on, the second that a USB destination device like a DAC is attached to the Wyrd. Unlike the iFi Micro USB Power, the Wyrd has only one USB A output so no split double A end USB cables can be used directly with this device.

iFi Mercury .5 meter USB Cable
The Wyred was connected to my computer with an iFi Mercury .5 meter USB cable. The quality of this USB cable was very apparent upon visual examination. The machined aluminum connectors with gold plated ends are quite impressive looking for a cable at this price. The Gemini has 3 custom-made metal oxide ceramic RF noise silencers. One is placed at each end of the cable; the middle filter can be moved to fine-tune the sound of the cable. I did find that movement of the center filter resulted in a slight, but perceptible difference to the sound. iFi claims that the Mercury cable adheres to the 90 ohm specification of the USB transmission protocol with just a 1% deviation from the 90 ohm impedance including the connectors and the cable.

I found this cable to be quite neutral sounding and very competitive with more expensive USB cables.

Does the Wyrd USB Decrapifier Improve the Sound?
I first evaluated the Wyrd with the Audioquest Diamond USB cable. I definitely heard positive sonic results using the MSB Technology Analog DAC. In general, the soundstage was larger with enhanced air and depth. There was less congealing of multiple voices and instruments when played with the Wyrd. The silence was improved with a deeper black background. Voices and instruments were smoother with a slight edginess removed. The bass had better definition and slightly more impact. I am happy to say that the Wyrd did no harm to the sound. Transients were not softened nor was there a brightening of the sound.

The new release of West Side Story with the San Francisco Symphony (PCM 24/96 and dsf 64) allowed me to easily hear the effect of the Wyrd on the sound of my DAC. Not only were the voices of the singers better focused, but the percussion was better defined with the Wyrd. The soundstage opened up significantly with the Wyrd when connected to the Analog DAC.

I also had a ripped SACD of the Mobile Fidelity release of Patricia Barber’s A Distortion of Love. The track "My Girl" presents Barber’s voice with reverb added in the studio. Using the Wyrd, the reverb was far more apparent to me with better focus of her voice along with a larger soundstage.

The Netherlands Chamber Choir recording of Bach Motets (Channel Classics 24/192) proved to be another good test for the Wyrd. With the Wyrd there was a reduction of subtle distortion or hardness heard with multiple voices in the choir along with a deeper and wider soundstage. The ambience of the recording venue was more easily discerned when using the Wyrd.

My findings using the Synergistic Research Galileo LE USB cable with the Wyrd were similar to that obtained with the Audioquest Diamond.

Sonic Comparisons with the iFi Micro USB Power
The iFi Micro USB Power is another very well made product housed in a very attractive aluminum case. iFi’s description of the Micro USB Power:

“To create a USB power supply that is ultra-quiet is an engineering feat in its own right. We went several steps further. The Super Regulator technology encompasses multi-stage and multi-order power purifying with filtering. We even commissioned a special, audio-grade USB power supply unit. The iUSB, with an excellent voltage accuracy of 0.5%, is even quieter than a 9V dry cell battery.”

“The iFi Micro USB Power is supplied with a high quality SMP wall wart and the device supports High Speed USB 2.0.”

Using the Audioquest Diamond and the iFI Mercury, I noted a number of similar findings as those obtained using the Wyred. But there were some differences that were readily apparent to me in my listening sessions. The iFi Micro USB Power had a slightly brighter sound quality with the Analog DAC. I also noticed that there was less reverberation and focus to Patricia Barber’s voice when she was singing the song "My Girl". The iPower had a bit more presence to the midrange and highs when listening to West Side Story. The Wyred had a slightly bigger soundstage and slightly more depth than that heard with the Micro USB Power.

Substituting the double A ended iFi Gemini USB cable for the Audioquest Diamond with the Micro USB Power resulted in a deeper black background and a bit less presence to the midrange and high end. The Gemini shares the basic construction of the Mercury, but has dual-headed A ends that totally separates the power lead from the audio lead until recombined at the B end. Unfortunately, I was unable to test the Gemini with the Wyrd as it has only one USB A output.

Some of you will prefer the midrange and high end presence of the iFi Micro USB Power as compared to the slightly more neutral sounding, at least to my ear, Wyrd. Using a filter or line conditioner with the power supply of the iFi Micro USB Power did diminish this slight presence. Perhaps the SMPS of the Micro USB Power is adding some noise to my AC power line and affecting the overall sound of my system.

The iFi iPurifier
This beautifully machined aluminum filter was inserted into the end of the Audioquest Diamond and the other end directly into the Analog DAC. The iPurifier cleans and filters the audio and power output of the USB cable just before it enters the DAC.

iFi claims that the iPurifier reduces the typical EMI noise of 39 dB at the computer to 34 dB. The iPower uses the same connector design as that found in the Mercury USB cable matching the 90 ohm impedance standard. The USB connectors in the iPurifier are gold plated and housed in a machined solid aluminum design that provides enhanced RF shielding. The iPurifier also removes DC offset and rebalances the USB audio. The iPurifier supports High-Speed USB Audio Class 2.0 to 384 kHZ and beyond.

The Sound with the iPurifier
I noticed obvious differences using the iPurifier with the Audioquest Diamond USB cable. In general, the soundstage was slightly wider with more apparent detail to the highs. There was a small improvement made to the bass definition and dynamic qualities of the bass. Focus and resolution of multiple voices were improved with the iPurifier.

Transients seemed to be a little clearer and sharper with the iPurifier.

Listening to the Netherland Chamber Choir Bach Motets, I noticed that the voices of the choir were more easily identified with less hardness to the sound. The soundstage was wider and deeper with the iPurifier. I also observed that the ambience of the hall was improved using the iPurifier.

I heard the same improvements to bass dynamics, better defined highs, and improved presence and focus of the piano listening to Monty Alexander’s Calypso Blues (Chesky 24/192). Background silence was a little darker with the iPurifier.

I did feel that there was a definite sonic signature to this device that added a small amount of highlight to the midrange and highs. Some might call it coloration, but I did not find it objectionable.

Substituting the Synergistic Research Galileo USB cable for the Audioquest Diamond resulted in quite startling results. I heard a softening of transients with slightly diminished dynamics from the bass and percussion. The presentation was smoother at the expense of detail. The dynamic quality of the entire presentation seemed to be compressed. I did hear a slightly wider soundstage using the iPurifier with the Galileo LE. The Galileo LE has its own UEF filter and it appears that adding the iPurifier to the Galileo results in too much filtering. If you don’t hear positive results with the iPurifier, it just might be the result of a less than ideal match with your USB cable.

The Ultra Fi Aubisque USB Filter
Ultra Fi states that their Aubisque USB Filter reduces computer noise passed down the USB cable when installed in-line with the USB cable at the type B end and directly plugged into your DAC. The Aubisque is made of molded plastic and of similar size to the iPurifier. It appears to be very well built. The Aubisque has a 2 layer circuit board with essentially 3 filters. A 1st order filter is used on the Ground, a 1st order filter on the VBUS 5 volt line, and a filter on the 2 data lines that deals with common mode noise rejection. Another aspect of the design of the Aubisque is that different gauges of wire are used in its construction that seems to have a significant effect on the resultant sound. Larry Moore, designer of the Aubisque, stated that his filter can reduce USB noise by 5 dB.

The Sound with the Aubisque
I heard a very slight enhancement of the soundstage using the Aubisque with the Audioquest Diamond. I did hear a reduction in overall hardness of the sound with enhanced clarity. Transients sounded cleaner and slightly more dynamic with the Aubisque. The background silence seemed to be slightly improved when I listened to music with the Aubisque. As I played the Netherland Chamber Choir Bach Motets, I noticed that there was a noticeable improvement in the sound of the choir with less edginess to the sound. The soundstage seemed slightly wider and deeper.

Listening to Calpyso Blues, the cymbals were better defined and cleaner sounding. The entire presentation seemed more dynamic with the Aubisque.

The Aubisque is very neutral and does no harm to the music. It doesn’t seem to add any presence to the sound, but appears to enhance DAC resolution.

As with the iPurifier, the Aubisque was not a good match with the Synergistic Research Galileo USB cable.

Comparison of the Aubisque with the iPurifier
The iPurifier presents a bigger soundstage and more presence at the high end than the Aubisque. Some will prefer the sound of one over the other depending on your DAC and system. I would say that the Aubisque has less personality than the iPurifier, but does not seem to have as great an overall effect on the music as the iPurifier.

Final Thoughts
The iPurifier, Aubisque, and the Wyrd USB Decrapifier all demonstrated a positive improvement to the sound of my system under certain component selections. Just how all of this plays out for you will depend on your DAC, cables, and even the computer utilized in your system. I often used the adjective “slight” to describe what I was hearing with these devices as these changes are not earth shaking, but could be perceived on my system. Perhaps the effects of these devices would have been larger had I used a less expensive DAC than the MSB Technology Analog DAC. While I feel that most computer audiophiles will benefit and enjoy using one or more of these devices, auditioning them in your particular system prior to purchase is most definitely recommended.

COMMENTS
tubefan9's picture

Interesting that lowering EMI noise will widen the sound stage.

Were you using the Schiit Decrapifier along side the iPurifier/ Ultra fi? (I'm feeling a little tongue tied with all these names, I cant imagine how difficult it was to write this review)

Steven Plaskin's picture
I appreciate the suggestions on the power supply orientation. For the record, the power supply was orientated properly in a Synergistic Research Quantum Line Strip. I also evaluated the iPower with the line strip plugged into a Synergistic Research Power Cell 10 SE MKIII. A JPS Digital AX power cord connected the two. Thanks Darren
Steven Plaskin's picture
I did try different combinations but didn't include the results- TMI ( too much information ) !
CG's picture

My amateur experience is that any time you get rid of noise in any form - whether unwanted acoustic reverb in your room, unwanted microphonics in electronics gear, electrical noise carried through the power mains, noise on the digital connections, or a dozen others - you hear more detail. That allows you to hear a better soundstage.

fmak's picture

I agree in general with the review of these products. The USB Power should not be used with the wall wart as there is a degree of hf emphasis, and should be powered from a really good 9V supply. This then does improve usb audio into different dacs significantly.

The Gemini is an awkward cable to use, especially when it is necessary to twist the B connector to fit in with the orientation of the socket. The sliders do have the effect as described but I would prefer being able to remove them to minimise the no of iductors on the cable and also to stop these from sliding when there is an incline on the cables. Two Mercuries with removable sliders may be even better.

The Purifier does clolour the sound and I do not find its effects acceptable, except when used with 'poor' usb connections. this has the effect of santitising the sound.

The Wyrd is not yet available here but sounds like a bargain.

CG's picture

I've used an iPurifier on two completely different types of USB DACs. In both cases, the sound *with* the iPurifier is preferable for both my wife and me.

This just shows - at least to me- that different solutions are needed for different circumstances. To date, nobody has made a bullet-proof USB DAC or a noise free source, although some are pretty darned good. So, the remedy varies from set-up to set-up. That includes the rest of the system, from AC mains to amplification to speakers to room acoustics.

In addition, people just aren't constructed the same way with regard to their auditory systems and how their brain processes and responds to the music itself. That should be kind of obvious since not everybody has the same taste in music.

It's great that companies are offering a wider range of options to optimize things.

ogs's picture

fmak, would you say the sound with iUSBPower and a good 9V supply is on the same level as Stevens description of the Decrapifier?

Frank Hardly's picture

Interesting review. I'm left hanging wondering (accepting all the caveats about individual system synergy)what you would actually spend money on to add to your own system. The Schiit seems to offer the most bang for the buck reading between the lines.

fmak's picture

When we discuss the effects of the devices, we are not just talking about how 'immune' the dacs are, buts also as importantly, how good the computer usb outputs are and how many usb devices are connected.

For best audio, there should only be one usb device connected to a motherboard output, and that is a usb audio device. USB power from the computer should also not be used.

junker's picture

The comparison might make more sense with a USB DAC such as the Dragonfly or GeekOut which draws ALL of it's power via USB.

Steven Plaskin's picture
I have a Dragonfly, but how do you connect an iPurifier or Aubisque to it? Same with the GeekOut. You could plug these DACs directly into the Wyred or iPower.
BEC's picture

I use the "B" to "Mini B" adapter which is provided by iFi with both the Gemini cable and the iPurifier. Snap it on the end of the iPurifier and into the Dragonfly. Works with my HRT Microstreamer which I run strait in to my Bryston Amp.

junker's picture

So we would need a female type B to a female type A?

$0.88 @ Monoprice =)

http://www.monoprice.com/Product?c_id=103&cp_id=10314&cs_id=1031401&p_id...

This is what you would need I think Steven?

-Josh

junker's picture

I'd really like to hear how the ifiUSBPower and Wyrd affect the USB DACs... esp. the Schiit for $99! ;)

CG's picture

At these prices, why don't you try it and let us all know? More opinions across more systems would be a great thing!

Steven Plaskin's picture
Perhaps I can revisit this topic again with less expensive DACs in the future. Thanks for your suggestions.
junker's picture

Cool! Definitely the best way to ascertain the potential impact of clean power on DACs that utilize the 5V for everything rather than possibly just the XMOS or other USB transceiver...

Either of these adaptors could be used with either USB DAC and your preferred reference RCA cables:

$0.44

http://www.monoprice.com/Product?c_id=104&cp_id=10429&cs_id=1042902&p_id...

AudioQuest (Nice because it is 90˚):

http://www.amazon.com/Audioquest-3-5mm-Mini-Plug-to-2-RCA-Adapter-Hard/d...

Habu2u's picture

Steven,

I've learned the Apple iPhone charger actually provides pretty decent output for a switching power supply - and probably better than the output from a computer's USB port. In addition it will output 1A vs. 500mA from a computer's port.

http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html

To do this upgrade all you need to do is plug the power leg into the iPhone charge cube, tape off pin #4 of the computer data leg, plug your usb Dac into the merged female port (of the Y Cable). Geek powers up and is detected by the OS and audio applications. The charger is 1A for it can provide about twice the maximum power of the very best USB ports which meet spec (500mA).

Required Supplies:
1. Apricorn USB Power Adapter Y Cable http://www.amazon.com/Apricorn-Power-Adapter-Cable-AUSB-Y/dp/B000JIOHDE
2. OEM Apple iPhone or iPad Charger
3. Electrical or Teflon tape to cover Pin 4 on computer connector

This usb power supply will set you back around $30. I use it with excellent results...

Credit goes to the LHLabs Geek Forum: http://lhlabs.com/force/geekdiy/2247-apple-iphone-charger-as-usb-power-s...
v/r Will

fmak's picture

to evaluate a $199 dac with a $199 power supply.

HQ dacs need to be used to identify the changes and the differences and it is noteworthy that an expensive dac can be improved using a better usb 'transformation' device.

plakey's picture

I'm curious if any of these devices matter (or make a difference) if one is using a USB -> SPDIF converter? And if there is any consensus about the pitfalls of USB in general as a primary way of streaming music to a DAC. I've never heard a USB DAC that didn't sound worse than the same DAC feed through SPDIF. But I have not heard an AYRE USB DAC which is supposed to sound amazing!!

fmak's picture

Yes

Habu2u's picture

I've learned the Apple iPhone charger actually provides pretty decent output for a switching power supply - and probably better than the output from a computer's USB port. In addition it will output 1A vs. 500mA from a computer's port.

http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html

To do this upgrade all you need to do is plug the power leg into the iPhone charge cube, tape off pin #4 of the computer data leg, plug your usb Dac into the merged female port (of the Y Cable). Geek powers up and is detected by the OS and audio applications. The charger is 1A for it can provide about twice the maximum power of the very best USB ports which meet spec (500mA).

Required Supplies:
1. Apricorn USB Power Adapter Y Cable http://www.amazon.com/Apricorn-Power-Adapter-Cable-AUSB-Y/dp/B000JIOHDE
2. OEM Apple iPhone or iPad Charger
3. Electrical or Teflon tape to cover Pin 4 on computer connector

This usb power supply will set you back around $30. I use it with excellent results...

Credit goes to the LHLabs Geek Forum: http://lhlabs.com/force/geekdiy/2247-apple-iphone-charger-as-usb-power-s...