• Bel Canto Design uLink USB to S/PDIF Converter Review

    Good USB to S/PDIF converters have been around for years, but the presence of great USB to S/PDIF converters is a fairly new phenomenon. The original Bel Canto USB Link was a good product when introduced in 2009. Since then new USB to S/PDIF converters seem to have hit the market every week. Several of these new converters offer the same or similar performance as products released years ago. In some cases the chassis have been upgraded to version 2.0 while the sound quality remains at version 1.0. A bump from 24 bit / 96 kHz to 24 bit / 192 kHz support by itself means nothing in terms of sound quality. In fact it can reduce sound quality because of the increased power draw and noise introduced by the high speed circuitry. The need for exemplary digital design has never been greater. The Bel Canto uLink USB to S/PDIF converter is a substantial step forward from previous Bel Canto converters and on par with some of the best converters available today. The uLink's unique features, great design, and great sound quality combined with its less than reference grade price point place it in a very sweet spot. It's far better than commodity converters and very close to reference quality converters. Computer audiophiles, without budget constraints, seeking the final 5% in sound quality may want to consider the Bel Canto REFLink and Berkeley Audio Design Alpha USB. Everyone else, myself included, should seriously consider the Bel Canto uLink.












    It's the clocks stupid


    In reference to campaign strategist James Carville's phrase it's the economy stupid , the uLink should be marketed with the phrase, "It's the clocks stupid." The uLink has other great design elements and features, but the Crystek ultra low phase noise clocks (CCHD-957 Series ) are the foundation upon which the uLink is built. In addition to the clocks the uLink filters incoming USB bus power with several dedicated power supplies to further improve sound quality. A unique feature offered by Bel Canto on its uLink and REFLink products is the ST fiber S/PDIF interface. This optical fiber connection passes only light from the uLink to the receiving DAC, eliminating the noisy electrical connection between computer and DAC. ST is a common name for the physical connector placed on the end of each fiber optic cable. The connector's proper name is Bayonet Fiber Optic Connector (BFOC). The uLink uses this connector with a multi-mode fiber cable. Milti-mode fiber, as opposed to single-mode, has bandwidth up to 10 Gbps with lengths as long as 2000 feet depending on the speed of the application and cable. Contrary to what I assume will be popular belief, the quality of the fiber cable matters. Some fiber cables actually decrease sound quality by transmitting less light causing higher signal to noise ratio at the receiving photodiode resulting in increased jitter. During this review period I was fortunate enough to have two DAC with ST fiber inputs, the Bel Canto DAC3.5VB mkII and the EMM Labs DAC2X. The DAC3.5VB mkII was designed from day one to accept ST fiber connections from other Bel Canto products. The DAC2X on the other hand designed its EMM Link (ST fiber) input as a proprietary encrypted DSD input from the EMM Labs transport and Sonoma workstations. Much to the surprise of EMM Labs the uLink works perfect with the DAC2X via fiber optics. The DAC2X's EMM Link interface has much more than 100 Mbps of bandwidth and very low jitter. In fact many Sonoma systems frequently use this interface with over 100 meters of cable between devices. I can't vouch for performance using this length of cable as the cable I used in this review was about 12 feet long. Bel Canto has used 15 meter long optical fiber cables and sees no problem going to 100 meters with the uLink. CA readers in need of a long cable between their computers and their digital components may find the uLink's optical fiber ST connection a great option.

    Rather than wax on about the specifications, build quality, and traditional component review items I punched up Bel Canto's John Stronczer via Skype for a quick interview about the uLink converter. In an effort to reduce superfluous questions, the following video is required viewing before readers can post comments below the review (only kidding).




    For Your Listening Pleasure


    Combining both the Bel Canto DAC3.5VB mkII and the EMM Labs DAC2X with the uLink over the course of the review period was a real treat. The DAC2X was runner up for 2012 CA Product of the Year and at the time I reviewed it the DAC was the best I'd ever heard in my listening room. The DAC2X has since been usurped of its number one position here at CA by the dCS Vivaldi DAC. At twice the price the Vivaldi damn well better beat the DAC2X. The Bel Canto DAC3.5VB mkII is also a stellar performer that competed wonderfully with the EMM Labs DAC2X and dCS Vivaldi DAC.

    The biggest surprise of the review period came when listening through the uLink to The Band's The Last Waltz Suite: The Weight featuring The Staple Singers. Readers who haven't heard this track or who may not be big fans of The Band should really get ahold of this album. I've listened to this specific track countless times through countless components in my system, but this time I heard something new. At 3:51 into the track I heard Mavis Staples clapping. I can recognize those hands anywhere. Only kidding. After hearing this for the first time I pulled up the video on YouTube and confirmed what I'd heard and saw that Mavis Staples was the person clapping. Subsequently listening to The Weight featuring The Staple Singers on other systems I could easily hear the clapping. It's one of those obvious things I can't believe I never previously noticed. The bottom line isn't that the uLink is much more resolute than my other components and enabled me to hear sounds not audible through components. Rather the uLink is a component that elevates one's listening experience to a level that produces exceptional separation of sounds and enables listeners to identify items that may be lost in the noise found in other components. Once those items are heard for the first time they become obvious on even low quality MP3s and YouTube videos.

    Listening to Xiomara Laugart's La Llave and Big Head Todd & The Monsters' Please Don't Tell Her through the uLink I heard deep and powerful bass. Both tracks feature terrific but different bass elements. La Llave opens with a powerful bassline that sets the tone for the entire track. If the baseline is reproduced without control, texture, and depth the track loses much of its appeal. The uLink doesn't hinder this bass from appealing to computer audiophiles. Please Don't Tell Her also opens with a nice deep bassline but continues this as a foundation throughout the track. The uLink's low noise approach enables listeners to hear this bassline prominently amongst all the other instruments and vocals. I listened to a couple Big Head Todd albums after removing my review hat and thoroughly enjoyed the signature baselines found on many of the tracks.

    The gloss and decay of Nat King Cole's voice in The Very Thought of You have become sonic elements I'm both addicted to and listen for when evaluating components. It's hard to believe that chain smoking Cool cigarettes before recording his vocals lead to Nat King Cole's lush signature sound. Nat had the voice that built Capitol Studios. Listening through the uLink I could hear his voice wonderfully reproduced in combination with the EMM Labs DAC2X and the Bel Canto DAC3.5VB mkII. Again Bel Canto's low noise approach with the uLink really shines as Nat's voice fades. The vocal decay heard when Nat holds on to words such as "The very thought of Youuuuuuuuuuuuuuu", when opening the title track of the album, sounds delicate and sucks the listener into the track. Following that opening line I was sold, sucked-in, and couldn't stop listening. Products that don't get this track right don't get my attention for more than ten seconds. It's an element that once heard right is addicting.

    Changing pace quite a bit I queued up Gordon Goodwin's Big Phat Band's album Swingin' For The Fences. The opening track Sing Sang Sung was great through the uLink. This isn't the type of track I use to listen for the tiniest of details. I use this track and entire album to listen for tone, separation of instruments, and punch. The uLink passed the Big Phat Band test without issue.

    Like a hired home inspector prior to the purchase of a new house a journalist must find some fault with a component in for review. At best the review is an honest assessment of a product that isn't perfect. At worst the journalist writes some fluff that the component's only problem is that it's just too good. I've yet to hear a product that's perfect. The Bel Canto uLink is no exception. Comparing the uLink's BNC output to its ST optical fiber output I noticed a slight rounded edge on transients through the ST fiber link. The sound could be considered smooth or even tube-esque during briefs moments of attack. I noticed this while playing Ottmar Liebert's track Along This Road: Kono Michi. Each pluck of his guitar has a distinct start and decaying stop. Through the uLink's ST interface the distinct start was a touch soft. Still great sounding, maybe even preferred by some tube or analog lovers, but soft nonetheless. This rounded edge or softness of transients was not present when listening through the BNC S/PDIF interface. In every system there are tradeoffs with different features. In my system with a battery powered server and USB interface the noise transmitted from my computer is extremely low. Thus, I prefer the BNC output of the uLink when it comes to transient attack. In other systems the ST fiber output may help eliminate noise so much that its faults can be easily overlooked.


    Conclusion


    The Bel Canto uLink sits in a very sweet spot between the budget mLink and the reference level REFLink. It features the identical Crystek ultra low phase noise clocks and ST fiber interface as the REFLink at less than half the price. Asynchronous USB and discrete power supplies are also among the reasons why the uLink sounds so great. In the last couple years great USB to S/PDIF converters have be introduced at a rate far lower than good USB to S/PDIF converters. Those satisfied with good performance must wade through an ocean of converters each offering a different but underwhelming twist on the same thing. Computer audiophiles seeking great performance without financial hardship should include the uLink on a small list of great converters with unique features, great design, and great sound quality. I highly recommend the Bel Canto uLink USB to S/PDIF converter and award it a place on the CASH List without hesitation.


















    Product Information:



    • Product - Bel Canto Design uLink
    • Price - $675 (mLink $375, REFLink $1,495)
    • xLink Comparison - Link
    • Product Page - Link
    • Data Sheet - Link (PDF)
    • Clock Measurements - Link (PDF)












    Associated Music:









    Associated Equipment:













    Comments 37 Comments
    1. dallasjustice's Avatar
      dallasjustice -
      Chris,
      Why didn't you ask John about how he took the "audio pimp" down? :-)
    1. DanRubin's Avatar
      DanRubin -
      Good review, Chris, thanks.

      Do your reference DACs have USB inputs? Do you get better sound using a converter to S/PDIF than going directly in via USB?
    1. guydebord's Avatar
      guydebord -
      Thanks, Chris. Always very good writing.
      But I wholeheartedly disagree that the Berkeley Alpha only provides the extra 5%, for me 5% is something you need to analyze and determine differences, to me the Alpha difference with the RefLink was so obvious that it was staggering and would say that it at least (in my system) provides 20% better sound.

      If we are talking about a value, the Audio GD DI-V3+PSU was (in my system) at least 5% better than the uLink, and it costs 50% less.... I know you never heard it, so its an unfair comment, I just want to draw attention to the word 'value', as it begs more comparisons to what is out there. Perhaps the uLink can really make sense if you have a BelCanto Dac and use the ST fiber connection, here I cannot comment because I never heard to it or the RefLink this way.
    1. Quest's Avatar
      Quest -
      Hi Chris,

      A few questions/comments:
      1. When you made comparison of the sound character of the BNC vs optical, I do think cables do factor in the difference.
      2. Do I take the above review to mean that you did like the uLink versus direct usb to the dacs used?
    1. Fritsveer's Avatar
      Fritsveer -
      Hi Chris
      Thanks for the review. I am interested as i am still debating the best connection between my computer (Mac) and my Dac (superuniti).

      Would you prefer, from a sound quality prospective, a wired internet connection to the DAC or a USB to SPDIF connection?
    1. Musicophile's Avatar
      Musicophile -
      Chris,
      Very nice review. Question: Did you compare the ulink to the mlink as well?
    1. Encore's Avatar
      Encore -
      Quote Originally Posted by Quest View Post
      2. Do I take the above review to mean that you did like the uLink versus direct usb to the dacs used?
      Yes, an important question for potential buyers (who probably don't have DACs w async USB) would be how close to real async USB directly to the DAC this product comes. Or, indeed, if using the optical input even betters the DAC2X's async USB input.
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      Quote Originally Posted by dallasjustice View Post
      Chris,
      Why didn't you ask John about how he took the "audio pimp" down? :-)
      Ha!






      Quote Originally Posted by DanRubin View Post
      Good review, Chris, thanks.

      Do your reference DACs have USB inputs? Do you get better sound using a converter to S/PDIF than going directly in via USB?
      Some have USB inputs.

      It all depends on the entire system from source to speakers and everything in between.






      Quote Originally Posted by Quest View Post
      Hi Chris,

      A few questions/comments:
      1. When you made comparison of the sound character of the BNC vs optical, I do think cables do factor in the difference.
      2. Do I take the above review to mean that you did like the uLink versus direct usb to the dacs used?
      All three interfaces, optical fiber, BNC and USB on a DAC sound different and measure different. The Bel Canto DAC doesn't offer USB input so there is no way to compare a direct USB connection versus the uLink.








      Quote Originally Posted by Fritsveer View Post
      Hi Chris
      Thanks for the review. I am interested as i am still debating the best connection between my computer (Mac) and my Dac (superuniti).

      Would you prefer, from a sound quality prospective, a wired internet connection to the DAC or a USB to SPDIF connection?
      I have no preference because there are so many variables. I would have to set a specific system up in my house and listen for many hours each way before concluding anything.






      Quote Originally Posted by Musicophile View Post
      Chris,
      Very nice review. Question: Did you compare the ulink to the mlink as well?
      No.
    1. findog3103's Avatar
      findog3103 -
      maybe I missed it but I don't see the optical cable listed in your associated equipment. I am curious which one or ones you used.
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      Quote Originally Posted by findog3103 View Post
      maybe I missed it but I don't see the optical cable listed in your associated equipment. I am curious which one or ones you used.
      I used a cable supplied by Bel Canto. All BC dealers can supply the same cable at any length.
    1. findog3103's Avatar
      findog3103 -
      Quote Originally Posted by The Computer Audiophile View Post
      I used a cable supplied by Bel Canto. All BC dealers can supply the same cable at any length.
      Got it. Thanks.
    1. Encore's Avatar
      Encore -
      Quote Originally Posted by The Computer Audiophile View Post
      The Bel Canto DAC doesn't offer USB input so there is no way to compare a direct USB connection versus the uLink.
      But the DAC2x has ... ?
    1. drambuie's Avatar
      drambuie -
      My deliemma is that my Imac is 20ft from my potential dac. From your review of the Unlink converter I get the impression the ST Fiber Input optical cable is the ideal solution to this distance issue. What about Toslink? Are there more than two Dacs with ST Fiber Inputs?
    1. Elberoth's Avatar
      Elberoth -
      Many older DACs come with ST inputs. I have once spoken with dCS Martin Reynolds, and he said that ST interface is prone to jitter.
    1. Lowlands's Avatar
      Lowlands -
      I remember the manual of my Wadia stating ST was to be preffered over BNC and toslink for sound quality....
    1. VandyMan's Avatar
      VandyMan -
      Is a Ref Link review planned? I'd love to see a roundup of 1-2K priced converters.
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      Quote Originally Posted by VandyMan View Post
      Is a Ref Link review planned?
      No.
    1. VandyMan's Avatar
      VandyMan -
      Too bad. Seems like there would be a lot of interest here.
    1. VandyMan's Avatar
      VandyMan -
      Also, your one word reply comes across to me as a bit rude.
    1. InnerGroove's Avatar
      InnerGroove -
      How many words are necessary to not come across as rude?