Ditch your USB cable for Toslink? Might surprise you!

I recently embarked on experiments with an updated USB cable between an Aurender N100h and a Qutest dac. (cables were Pangea, Curious and DH Labs) Bottom line, it  most definitely revealed improvements but also exposed some flaws. So I looked into other tweaks to improve the chain...reclockers, decrapifiers and the likes. All these devices designed to fix inherent issues with USB. So I had the "duhhhh" moment and thought instead of fixing it....replace it.

I went out on a limb and got Aurender's UT100, a device which converts the USB output to Toslink (best option as the N100h only has usb out). I connect a modest Audioquest Cinnamon cable to it and I've been testing and burning in this new device and the input on the dac for several days now, Redbook all the way up to 24/192. And I must say I'm impressed, really impressed. I'll summarize my experience by saying it's just as detailed, but with a more relaxed presentation, no digital "grunge". This is the first time I've even considered trying the incisive filters on the Qutest.

I think Toslink is looked down on as a digital interface, but I'm seeing some big advantages to it now.

  1.  You gain 100% isolation, it totally "air gaps" your dac from every form of interference. I've personally experienced some Bermuda Triangle kinda weird issues with USB and there have been lots of posts lately regarding this. Fiber puts an end to that....period!
  2. The price of admission is downright cheap, most streamers and dacs already have the connections and I don't think you have to pay a lot for a quality fiber cable.
  3. On some dacs it's generally accepted that the SP/DIF connections sound better than their USB counterparts. I've also read that disconnecting the USB cable from a dac, turns off it's internal clock and associated circuitry, thus less noise internally.....?? I have no clue but what I am warming up to is the idea that I want to stay away from USB. I've had great results with coax too, going back to my Theta and Sony ES days, but Toslink is cheap, allows long cables if needed and does truly isolate the dac. 

I'd encourage everyone to just try it, perhaps your equipment will respond favorably  like mine did. I'd love to hear other's experiences, especially Node3 owners. I'm planning on getting one for my office rig.




@lordmelton Thanks for the link, I think I'd stumbled on their converters during my research of this. While my Chord dac doesn't support I2s directly, here is a quote from Rob Watts himself. As ALWAYS, the devil is in the details, and the manufacturer's implementation trumps all. 

"Yes traditional SPDIF receivers are not good at recovering the SPDIF and creating a clock, as they rely on an analogue PLL - and the data itself modulates the clock, so you get signal correlated jitter which is extremely audible. But my SPDIF receiver is all digital, and relies upon the low jitter local clock, and does not create signal correlated jitter. The SPDIF receiver creates I2S data, with zero signal correlated jitter; plus a word clock, exactly as if it was transmitted via a real I2S connection.
But, the word clock - whether from a direct I2S or SPDIF, still will have source jitter. And this must be eliminated - and that is the job of my DPLL, which completely eliminates any source jitter. So there is absolutely no benefit in using I2S".

So who the heck knows? I'd imagine every decent dac has a similar SP/DIF implementation as Chord. What did steer me in my direction was simplicity. One cable, no extra boxes with more power supplies (perhaps even benefitting from LPS). It can get crazy pretty quick, this set up from Audiowise really started to point me to fiber: Audiowise SRC-DX


I have to say that I am skeptical about converting usb to anything else.  The USB is still in the system so if it is adding issues, putting another cable and adapter downstream doesn't get rid of hem.  You'll get a different sound I guess, but you haven't eliminated the evil that the USB is adding.

Now I'll disclose my opinion about USB.  USB is not evil.  It suffers from attacks by people selling competing technology or cables for competing technology.  


USB isolators are relatively inexpensive, but sometimes DAC's don't really like them.

Real shame that we still have issues with ground loops in USB or coaxial connections.

Well I wouldn't say it's evil, just that there may be advantages to other connections in some systems, and a necessity in others. The Bermuda Triangle weirdness I mentioned earlier was a MacBook Pro running wireless and on battery that made a horrendous noise connected to an Arcam irDac via usb, music didn't even have to be playing. Sounded like a ground loop on steroids. How is that even possible? But an optical cable made the problem go away. 

@carlsbad In my case the only streamer output is usb, so I had no choice but to try a converter if I was going to use a different input on the dac. Ideally it would have been toslink out > fiber > toslink in. I do however think there is potential with some of these decrapifiers, reclockers or converters. In theory a flawed signal goes in and a newly minted "perfect" signal goes out. You could very well be right though.

My only point is, I like many audiophiles, tend to snub our noses at toslink. What I'm hearing now has really changed my opinion of that. Honestly I didn't think it was capable of this high a level of performance. Most streamers and dacs already have the connections, if yours does I'd give it a try. Digital audio is like a box of chocolates so maybe you'll like it in your system, maybe you won't. Mine is staying.

@treynolds155 USB is ubiquitous in modern HIFI and unfortunately we're stuck with it until more mainstream manufacturers like PS Audio adopt I2s.

Since we can only play native DSD over USB and I2s, these are our options, unless DSD is not important to the user.

For the doubters out there I2s HDMI sounds differently from I2s RJ45, I have had best results with RJ45.

Like yourself I experimented with many options to reduce USB jitter but nothing has worked as well as converting it to I2s.

So, good luck with your research, bits are not bits.


I'd like to see more choices in streaming dacs, all rendering taking place within, avoids complexity and possible mismatch. As things stand, dac and streaming expertise far too segregated. 

The OP omits the clock synchronisation in USB that slaves the server to the DAC. A well clocked USB asynchronous connection with a good cable in normal circumstances is superior to Toslink.

@antigrunge2 Not being argumentative, strictly out of curiosity, but why do you think a well implemented USB setup is superior....higher bandwidth potential?

I thought the same thing until recently too, but I can't ignore the results I'm getting now. I really think this is very much system dependent, much like the balanced vs unbalanced cable debate. I certainly don't think Toslink is the end all interface. 

It's also interesting that the highly regarded Berkeley dacs don't even have USB as an input option. They do sell a $2,000 outboard USB to AES or SP/DIF converter though, and Innuos has their PhoenixUSB reclocker at $3,500 .....YIKES. 

The deeper I dig into all this, the more I realize how much I don't know. 🤔


Assuming a properly implemented asynchronous USB connection, the Dac slaves the server to its clock, i.e. the Dac’s clock controls the chain. Assuming a high quality clock in the DAC this ascertains absence of timing errors, aka jitter. While the same can be achieved by retrieving the server’s clock signal from an AES/EBU, SP/Dif or optical connection it assumes a very good clock at the server and absence of noise in the transmission of the clock signal. Where USB gets a bad rap  is on the 5v DC line included in the protocol. If the DAC doesn’t need the 5v line of its handshake with the server, this can be disabled just by putting a sticker on Pin1 in the USB plug. Otherwise good dual pronged cables exist to pass a clean 5v signal from a separate LPS to the Dac.

If one was to try one out, does this fall into the 1.5 meter minimum like SPDIF cables?


there are divergent views on that one: I keep my USBconnction as short as possible. John Senson at Uptone sells a one piece USB fixed circuit board connection. The SP/Dif minimum limit is to avoid reflections in the cable. Best I know this does not equally apply to USB.


I talked to DH Labs and they said as far as USB cables go it doesn't matter, they recommend keeping them short as possible. 

I've got a .5M Wireworld Supernova 7 Toslink coming in tomorrow to try out. I just like the idea of the stranded borosilicate glass vs the plastic. 

You're welcome to try my 1M Audioquest Cinnamon, just pay shipping.

To say that any one digital connection is superior to another is foolishness. USB quality depends on both server/streamer and dac implementation of it, don't need decrapifiers if implemented correctly in both. If usb implementation in these devices provides galvanic isolation, optimized clocking and isolated power supply you have first rate usb. Only then can you compare to optimized various other schemes and have valid results.


As I mentioned previously, it would be nice to have more streamer dac choices, if designer had great expertise in both rendering and digital analog conversion we could avoid non-optimized and/or mismatched streaming components.


USB gets bad name because very few have heard real optimized usb. While there are a decent number of dacs with, extremely few servers have, vast majority connect directly to motherboard, terrible implementation. Berkely understands this, so they avoid altogether, Innuos Phoenix admits as much for the Innuos servers. Only servers with usb galvanic isolation from motherboard, high end clocking and lps are optimized usb out servers. How many out there, virtually none apart from atx  motherboard machines and a few top top flight from the likes of Wadax, Taiko. Why do you suppose so many use streamers and various usb decrapifiers?


The usb decrapifiers are only band aids, one must get first rate streamer along with dac optimized for usb to really hear usb potential.



@sns  I've been very clear that I don't think Toslink is or should be the end all digital connection. What I am asserting is:

  1. Optical has at least the potential of avoiding 100% EMI/RFI, ground loops, magnetic and any other forms of interference. No matter how careful we try to be, take a look behind your rack and see if any problems could exist.
  2. Toslink MAY surprise you with its sound quality. Again, I always assumed it to be subpar. I was pleasantly surprised.
  3. Your system may or may not benefit and will most certainly be system dependent. The fiber transceivers and SP/DIF clocking implementation would certainly have to be up to snuff.

By your points, all but a select few products have nailed USB down to perfection, so wouldn't it be foolish not to try a different connection means? Especially if you have or are thinking of trying the band aids as you so accurately put it.

Thanks everyone, but I was wondering about the Optical cable being 1.5 meters, like the other SPDIF cables (Coaxial, BNC and AES/EBU) recommended lengths. 

I've used a lifatek glass toslink with a Logitech Touch via toslink into a dac and I always was surprised at how good it sounded.

I am a big Aurender fan. I own two of their streamers… including their flagship… which is truly incredible.. the sound quality is equivalent to my really high end audio end. 

In general, optical connections are inferior to SP/DIF, AES and USB. The reason is that most components use inexpensive electrical to optical or optical to electrical converters on their components. I am sure Aurender has created a converter that takes advantage of the ability to ditch noice and other issues. The result in your system will depend on the receiving component.

So, if you have components that you are not going to be upgrading and want to see if you can get more out of them… it’s only $300… worth a try. Certainly worth a try. But I am sure it is very system dependent.


Thanks for sharing. Really interesting product.

Posted these pics so everyone can see what you're talking about.

It looks really neat.

Yeah that's the one I have, got an excellent open box deal online for $170. Yet when I got it, the box was still sealed. It's a hefty little beast and I also assumed the Aurender sound quality when I purchased.

I was originally thinking of trying coax with this device, the UC100.

Aurender UC100


It's strange that these devices aren't listed in the website menu.

Hopefully we'll see an I2s converter or output soon.

@lordmelton From their mainpage, click on the "Audiophile" menu and they are listed towards the bottom of the dropdown. I agree on I2s output, seems like that is an emerging interface with a lot of potential. 

It'd sure be nice if all this was more standardized. Like: INTERFACE A is entry level, INTERFACE B is the next step....and so forth. But we all know that's a pipe dream. Way too many variables in the mix.

Excuse me but I’ve never found a great deal of value from this guy’s videos. Inevitably the idea/word ratio is very small. What we learn in this video is that different USB cables can, in fact, sound different. However, unless you’re a graduate of ASR University you knew that already.

What he doesn’t point out is that the best USB cable for a person is system specific. He likes Supra and Curious. I’ve tested Supra against the less expensive AudioQuest Pearl and much prefer the Pearl in my system. It’s not close. As for Curious, its principal claim to fame is separating the 5V cable physically from the signal cables. That feature is a large reason for its high price. But if your USB conversion uses its own power as mine does, that feature has no value whatever as there is no current in the 5V line.

For a comparison of USB cables that I found useful, but with which I could nit pick, see this.

i quite liked it... he does take you through his approach and his thinking that led to how he tried to control and compare, and i think he really dispels the notion that its all 1 and 0's so it is all bound to be the same

furthermore i like that he is careful is not overstating his conclusions, and he does say that all his qualitative judgements are of course just that... subjective and to his own taste

too many yt-ers say stuff without basis and are imprecise, whereas this fellow tries to be squeaky clean in explanations and methodology, does not overstep...

I'll have to check out this video, I've also read quite a few USB shootout reviews and I find them very interesting and informative.

So for the second time this week I get delivery on an open box bargain...that's brand new. 👍 The Wireworld Supernova 7 stranded glass Toslink cable sounds stunning compared to the Audioquest Cinnamon. Anyone reading this could pick out the difference in a blind test 100% of the time.

My expectation bias on this was low but I'd read very positive reviews, found a "open box" deal at Music Direct and said why not try it. So not only do we have the "it's just 1's and 0's thing...it's also just light. How the heck this thing can sound so different is beyond me but it's made a bigger difference than any other cable change I've tried, analog or digital. 

It's funny how when I have big expectations of new equipment/cables, I'm usually disappointed. And the opposite when I don't expect much. 

@treynolds155 I was introduced to WireWorld cables this year and I've been astonished how good they are.

WW Starlight 8 CAT 8 is a bargain Ethernet cable and the Starlight 8 Platinum CAT 8 is phenomenal in a higher price bracket.

@lordmelton Right! It makes me want to try some of their power and analog cables as well. Their USB cables always seem to be in the mix of cable discussions too. Audio Envy is another company that intrigues me, so many great choices out there. 

Digital cables most certainly do matter, I figured they did but never imagined how much. I was dead wrong!

folks here by and large know this, but of course digital cables affect sound... they are carrying analog voltages that mimic 1-0 step functions... at extremely high frequencies... ethernet and usb cables have wire pairs within them that carry those signals... in both directions, plus more...

I didn't mean to preach to the choir 🤐 I have read some pretty outrageous things from naysayers on this site though...especially regarding potential gains with optical cables. 


I have used the Wireworld Super Nova 7 glass optical, and it sounds great. I use it on my cd player used as a transport. I use a AQ. Coaxial on my streamer.

To me, the coax has a tiny bit more sparkle on the treble frequencies, and the glass optical is a little more on the warm side. I like both.

The largest selling cable companies are WireWorld, Transparent, and AudioQuest. This was from a survey on an audiophile forum…. Had a few thousand participants. I use almost exclusively Transparent, with one AudioQuest and Cardas power cords. I have several WireWorld and DH Labs spread across my other couple systems.

Toslink is fine if you can deal with its designed limitations. A long time ago before Toslink became the "standard" for optical cables, there was a better, much higher bandwidth optical cable made by AT&T called AT&T Glass. Of course it never caught on because for the time period it was overkill and now it is history, while Toslink (by Toshiba) did catch on (it was cheap) and is still here.

As long as you are happy to live within its DESIGNED limitations it is fine to use.

24/96 is the theoretical limit of TOSLink (it was designed for 48k) However, there are a lot of transceivers out there that, with good cables, can reliably pass 176.4k or even 192k. None (or almost none) will pass 352.8k (DXD and/or double rate DSD via DoP.)

Galvanic isolation is definitely a good thing. Pity that AT&T Glass isn’t still here.

Seems to me the negativity associated with Toslink is a hold-over from days long past, when it sucked. Some DAC designers (Rob Watts comes to mind) managed to figure out how to implement it with great results some time ago. Back when Chord released the first iteration of their Qute series (HD) Rob posted on the topic (Head-fi IIRC). Some naysayers gnashed their teeth and dismissed the idea Toslink could sound good, even argued with him. It was fascinating in a car-wreck kind of way. I still have my Qute (upgraded to EX) and use it on occasion with Lifatec’s glass cables, which easily handle a 24/192 signal. (The plastic variety I’ve tried all maxed out at 24/96.) And I have other DACs whose Toslink implementation sounds great. I think it’s been figured out.

Torq (at one time at least) seemed to really like lifeatec but I returned it after comparing it to my dulcet AQVOX toslink but still preferred a hookup with the  Requisite D3r coax reviewed at audiobacon.net. I plan to order soon the affordable Sys Concept toslink cable mentioned by currawong to compare with the Requisite. 

The quality of toslink nowadays is a direct function of the quality of the server‘s clock since that is what governs what the DAC receives. Small hint: USB based servers don‘t pay much attention to the clocking since in USB it‘s slaved to the DAC.

Eliminate the digital cable alltogether (streamer dac separates) and get a great sounding streamer+dac combo unit.

But, apparently, some sales guy theory crafted/ told all the dudes that streamer dac separates lifted more veils (Not!!) ....and the dude fiddles with an unnecessary extra stupid cable and box until the squirrels in his head run wild all day long.