USB yet again

“Hopefully the industry comes up with a better solution.”

@antigrunge2

It is very unlikely to see a groundbreaking advancement in the areas of USB, AES/SPDIF implementation. These protocols, IMHO have matured and may’ even reached their maximum potential. As you have mentioned, the industry is fast moving and trending towards Ethernet based DAC’s with embedded streaming client (renderer). There are some very high quality offerings from Grimm Audio, Merging Technologies, Weiss Engineering, DCS, and Bricasti. The current trend is, simple one box DAC/streamer/Pre solution. Just optimize the Ethernet path by adding a high quality Ethernet switch/LAN cables and you’re in business. The performance of these one box DAC/streamer is getting awfully close to a separate DAC and Streamer setup.

I recognize, there is always going to be those who wants the separates for flexibility and the last word in SQ :-)

As far as I’m concerned, my days of fiddling/optimizing the USB or AES/EBU supported audio devices are ancient history. 

@lalitk 
 

agree with your assessment. It seems though pretty damning that both on Ethernet and USB even on high end equipment you have to engage in extensive optimisation efforts before you get a decent result. As I said the single box solution can be seen as a capitulation.

Hopefully the industry comes up with a better solution.

This "problem" has been solved in the marketplace (by Ted Smith) for at least 8 years.

Sorry you missed it.

@fuzztone 

care to be less opaque and dismissive?

USB is criticized by those that market an alternative and those that believed their marketing literature.  USB is not inferior.

True words @carlsbad

On some DACs the inputs sound different with whatever cables you have so "experimenting" is warranted. Or change DACs.

I have a cheap one the sounds identical on Coax and USB while inferior on Toslink.

 

 

agreed.  I've never had a toslink that I thought sounded good.  many high end DACs seem to be built around a preferred input and often it is USB.  I haven't used Coax for a while.  

When I opted for a re-clocking and galvanizing component between the USB and DAC, my sonic quality sky rocketed. 

Ted Smith, PS Audio DirectStream DAC inventor uses / used USB on the original DirectStream DAC (there’s a new version now with galvanic isolation). Ted believed that the biggest issue with USB is the noise from the 5V power generated by the source. Unfortunately the DAC requires the 5V to be recognized but an inexpensive work around is available. A powered USB 2.0 hub and a power blocker adapter removes the computer’ 5V allowing the hub provides its own.

My experience is that it improved the sound quite a bit. I2S into the latest version of the DirectStream is probably better but defiantly not what I would call an inexpensive upgrade.

asynchronous USB is the only protocol synchronising the server’s and dac’s clocks

Confused.

Can you explain how does an asynch protocol synch two clocks?  Hint: it doesn't.

AES/EBU may have better noise rejection but has imbedded clock signal,SPDif is outdated as well as speed constrained

confused again.  AES/EBU is fundamentally SPDIF that is 1) balance and 2) contains optional metadata.  Speed constrained?  Not for the vast majority of formats and oversampling in even remotely common use....

 

 

Oh dear!    The agonies of going digital.

@itsjustme

technically speaking it slaves the server’s clock, i.e. data is requested by the dac rather than the server sending it on its own clock.

I stated that SPDif is speed constrained, not AES/EBU.

+1 for USB

This hobby is similar to running a manufacturing plant, it’s a game of bottlenecks in a quest for velocity/ perfection. Each rectified bottleneck, creates another bottleneck, as it can only be the case. At some point the listener’s hearing will become a bottleneck, and is/will be assisted/solved as technology advances. The flow will evolve and continue.

Mapping and measuring the flow of a manufacturing facility may be easier. Either way, solving the impediments will always be a challenge, otherwise they would not be impediments.

The issue to me is one of priorities, as resources (time) is limited, and so far, as far I know, the bottleneck of death continues to elude us, at least on planet Earth.

 

Sometimes I feel the goal of this hobby is to take a picture of a painting that is superior to the original work.

Optimal usb implementation requires quality rendering at both streamer and dac. This means usb boards with nice power supplies powered via dedicated power supply and top flight clocks on these boards. Far too many streamers are let down by less than optimal usb implementation, reason why so many find various usb filters and/or separate/dedicated streamers with top flight usb rendering to be of benefit.

I continue to rail against so many off the shelf streamers implementing less than optimal usb rendering, really not that difficult or expensive to do. They could add this as standard or upgrade option for aprox. $1-1.5k. I don't know, perhaps they don't have the capability to do this, The only streamers I'm aware of that offer quality usb rendering are Wadax, Taiko and Aurrender, and Innuos as separate box. Ridiculous IMO, leaving so much potential on the table!

+1 @uncledemp 

@uncledemp 

Enjoyed reading your post. Our systems are true reflections of how that painting should look (replicated) in our environment. I think for many of us, it’s the pursuit of perfection more gratifying and fun than the actual result 😊

USB is not inferior and offers superb sound quality in my opinion.  As always it depends on implementation and other digital supporting elements in one’s front end.   

@lalitk 

Yes sir, agreed. 
 

Best-

@sns 

my point, precisely. I also steuggle with dependence on cables and cleaned up power

One can perceive the complexities of streaming as a burden or a delight. I've found it to be much more delightful than burden, especially as the vast majority of my efforts have gone in direction of better SQ. Devoid these complexities I'd be pretty much in static position in regards my system.

 

Much of what makes pursuing audiophile hobby worthwhile for me is experimentation, streaming certainly provides that!. I'm getting to point where my audiophile bucket list is rapidly emptying, question is can SQ alone provide for all my audiophile needs? Over nearly thirty years, the process of building and optimizing audio systems has been pretty much as fulfilling as the enjoyment I get from countless listening sessions.

@sns I agree and once one has synergy in their digital front end the worlds of music unfolds. 

@antigrunge2 

I’m not getting your reference to SPDIF being “speed constrained”- how is this different when compared to AES?

@designsfx 

I am not aware of any SPDif connections faster than 192KHz, conversely double AES/EBU can run at 384MHz

👍  I wasn’t seeing anything about doubling AES in the thread. Thanks!

I was perfectly satisfied with my Node 130 using USB to my Denafrips Pontus II DAC. Started reading threads like this, and after checking with Alvin Chee at Vinshine, I decided to add a Denafrips Iris DDC between the Node and Pontus.

The Iris optically and galvanically cleans and re-clocks the data, and then outputs via I2S to the Pontus. The sound improvement was immediately noticeable even before the Iris and cable had a chance to settle in. Why I keep reading these threads

On one hand, what shall matter is the final digital to analog conversion, inside a properly designed and manufactured DAC. All those intermediate digital-to-digital converters, theoretically, shall not affect SQ.

On the other hand, I keep seeing accounts of SQ improvement after a DDC was inserted in the digital path.

Then, of course, we have posts like that on ASR regarding DDC:

https://www.audiosciencereview.com/forum/index.php?threads/do-we-need-a-ddc-or-is-it-bs.33949/page-2#post-1358738

"I’ve done extensive A/B testing and measurements with these. If properly blind tested, these didn’t make any difference with any of the DACs I tried"

What’s going on?

Upon closer look, it appears to me that most of such SQ improvement accolades come from owners of R2R DACs.

I looked at descriptions/specs/reviews of three of them, which I encountered most often in users testimonials:

https://www.denafrips.com/specs-enyo

https://www.denafrips.com/specs-pontus

https://www.denafrips.com/specs-terminator-plus

All three use "Proprietary USB Audio Solution via STM32F446 Advanced AMR Based MCU".

What is STM32F446? Here is the spec:

https://www.st.com/resource/en/datasheet/stm32f446re.pdf

What counts the most from my perspective is the CPU performance of that chip. It has one core, frequency of up to 180 MHz, and instruction efficiency of 1.25 per clock. So, it is roughly an analog of Intel Atom processor operating at 0.225 GHz. Pretty slow. The chip’s price reflects this - less than $10 per unit in quantity:

https://www.mouser.com/c/?q=STM32F446

Let’s pick some cheap contemporary oversampling DAC and see what kind of CPU it uses. For instance, S.M.S.L Sanskrit 10th MKIII, which can be purchased for $139. It uses XMOS XU-316 chip. Here’s its spec:

https://www.epsglobal.com/Media-Library/EPSGlobal/Products/files/xmos/XU316-1024-QF60B.pdf?ext=.pdf

This chip is quite a bit more advanced. It is not same yet similar to the one used in $17,500

https://www.suncoastaudio.com/products/aqua-hifi-formula-xhd-dac.

It is approximately equivalent to Intel Atom processor operating at 2.4 GHz. That is, it is over 10x more performant than the chip used by the Denafrips DACs.

Please note, I’m not discussing chips used for digital-to-analog conversion per se. The chips I discuss are used to deal with USB protocol, and to presumably implement First-In-First-Out (FIFO) buffer for the digital samples, enabling their subsequent re-clocking.

Could it be that the Denafrips DAC has to use a simplified FIFO buffer? Either in terms of length, responsiveness, or something else, because their CPU performance is less than 10% of that of a cheap contemporary oversampling DAC?

I tried to find measurements of the Denafrips DACs that could shed some light on that. Turns out that in Non-Over-Sampling mode (NOS), objective measurements of one of then are not exactly impressive:

https://www.audiosciencereview.com/forum/index.php?threads/review-not-so-positive-posted-of-denafrips-aries-ii.10906/

If such distortions were mostly a consequence of the DAC architecture with not overly precise resistors used, then insertion of DDC wouldn’t likely improve things - it wouldn’t affect resistors.

Since the DDC insertion does improve things, there is a reason to believe that the excessive jitter caused by the limited FIFO implementation might be at play. Or perhaps something else related to timing precision.

If this hypothesis is correct, than the DDC effectively adds a good implementation of FIFO in front of the DAC, thus ameliorating the DAC’s FIFO imperfection. Please note that this is just a hypothesis. Would like to hear your opinions about this.

One can perceive the complexities of streaming as a burden or a delight.

@sns Totally agree, but I think I’d substitute “delight” with “unbridled opportunity.”  I mean, this stuff can just get better and better almost seemingly without bounds if you’re willing to put in the thought, effort, and $$$.

@vthokie83 My experience running an Iris into my Musician Pegasus absolutely mirrors your experience.  Immediately noticeable and this with a cheap little 6” Monoprice HDMI cable.  Amazing, although maybe our DACs are set up to be optimized with the i2S input so I have to submit that as a variable.  Maybe other DACs prefer other inputs, but I’m all in on i2S.

Fair, You have some logic to the reasoning, but is above my understanding of electronics. I do know that the reports I have seen (or witnessed in my system) with a DDC or re-clocker working well were all from R2R ladder DACs, but from several different manufacturers (Denafrips, Musician, Holo Audio, and a couple more). Whether it is due to a FIFO limit, or the benefits of I2S, or some other reason I cannot say.

Soix agreed, I tested a friend's Pegasus and Aquarius in my system, and the results were the same.....but as before they also would have benefitted from I2S. If you're thinking of upgrading your HDMI, my reference is an Audioquest Vodka 48 8K, but the Supra Cables 2.1 8K and DHLabs HDMI 2.1 10K sound great as well.....both under $100

@vthokie83 

A DDC reclocks the USB connection. Therein may lie the principle benefit to SQ, probably not in using another port on the DAC.

Anitgrunge,

Yes I know the Iris reclocks and isolates (galvanically and optically) the signal, and I am sure this is the majority of the sound improvement. I have compared the digital coax versus the I2S, and found the I2S to be superior.....as have others. Is it a false sense of improvement? I don't know, but I'm sticking with the I2S

@vthokie83

I am not disputing what you’re hearing from the inclusion of DDC in your setup. But I believe the effectiveness or need for a device like DDC is largely depends on quality of your source and downstream components. If you use high quality components then a device like DDC is redundant. For example, It would be interesting to compare Node + Iris with Aurender N100 or N150 feeding your Pontus DAC.

Laltik, certianly not thinking you are, I've found your posts helpful and objective in the past.

That comparison would be interesting, and my hope is to one day own a Aurender N200 or whatever replaces it when I have the funds available. I would also like to upgrade my DAC someday, something like a Holo Audio May DAC KTE or Denafrips Terminator Plus; or whatever is best at that time of affordability. I do have access to an Aurender N10, but I won't test it lest I start lusting after something I cannot yet afford to add

@vthokie83

Thanks for your kind words. As others have reported, N200 with May or Terminator + DAC would be a formidable pairing and substantial jump in SQ over your existing setup. You’re wise man, I wouldn’t recommend N10 audition either unless you’re prepare to write a check. N10 is a remarkable player and if I may say so, a steal on used market. It has a very effortless, relaxed and detail presentation whereas N200 leaned towards more energy, livelier and detailed presentation.
Good luck in your journey and happy new year!

Thanks to all on this and various other threads who have been so helpful and illuminating in my search for information to level-up my streaming situation.

I’m definitely pretty budget constrained but am looking at either the Aurender N100 or Innuos Pulse on the high-end of the spectrum (for me) or the Innuos Pulse Mini on the lower end.

regarding USB, both the N100 and the Pulse are USB out only streamers.

Some here have said that finding the right DAC with a great USB implementation would be key in terms of getting the most out of such a streamer.

What are some of these DACs with a good USB input.

Neither of my DACs have USB…Border Patrol SE-I and Denafrips Ares ii.  I do have the Denafrips Iris DDC however which I could feed from one of the aforementioned streamers before the DAC, but I’m not sure of that would be extraneous on such a quality unit. 
 

Would love to get some feedback on that potential situation

thanks

JS

@j_andrews Look for Amanero or XMOS usb board in dac, not aware of any other top flight usb implementation on dacs.

 

I had Singxer SU6 at one point, never even bothered listening to it as research and logic made it moot point to even bother. Added complexity, DDC do have issues, even the SU6 benefited from modifications and even more complexity. The other thing remaining in favor of using usb vs I2S was optimal usb implementation in both streamer and dac, point is stick with best ports on streamer and dac. Agree with Latik, the best streamers negate the need for add ons like DDC, they provide top flight rendering, DDC superfluous. In can see how DDC could better streamer with less than optimal rendering or streamer/dac mismatch with optimal ports. AES/EBU should also be considered a contender, although not much talked about, Antipodes claims this best output in K series streamers, came very close to purchasing. At some point I may get around to trying various JCAT and Pink Faun PCIe cards in my streamer, I2S and AES/EBU both available, along with the more usual usb and network cards.

@j_andrews

A bit of clarification, which streamer you’re currently using and ARES II should have USB input along with SPDIF.

You got two reasonably good sounding DAC’s. I am in a camp where both DAC and Streamer quality matters. I am not going to get into a debate which carries more weight. If you’re deferring your DAC purchase then I would focus on either Pulse or a used Aurender N10. Both of these streamers should offer beautiful pairing (SPDIF output) with SE-I and USB or SPDIF out to Ares II now and with whatever DAC you choose down the road.

The Pulse Mini or N100 would be an intermediate step if you’re considering a DAC upgrade down the road.

+1 on @sns recommendation of Amanero or XMOS usb board in dac.

Thanks all,

Yes the Ares has USB, sorry I was having a lapse of memory.

I am currently using an Ifi Zen Stream w/ LHY linear 12V supply > Curious USB cable > Denafrips Iris DDC > Lifatec glass fiber optic cable > Denafrips Ares ii (or Border Patrol Se-i via coax from the Iris)

To answer your other question , I’d like to keep my Border Patrol and eventually upgrade the Ares ii AFTER getting a better streamer than the Ifi.

Surprised to hear you say that the N100 would be an intermediate step.  I was under the impression that it was essentially Aurenders scaled down streaming only / USB-only option and would be up against the Innuos Pulse.

I also need to really look at the user interfaces for each brand but I hear they are both superb. 

@j_andrews

I’ve heard good things about iFI Zen except the subpar interface and poor customer service. My comments about N100 was in the context of you considering DAC upgrade. The N100 is now 7 plus years old compare to newer, improved Pulse series. As good as is N100, I am reluctant to recommend due to its age and USB only output. I would’ve mentioned Aurender N150 along with Pulse but N150 only has USB out which again limits your options. So if you’re considering spending <$3500, Pulse or N10 despite of his age makes more sense to me.

If you can stretch your budget, consider Aurender N200. It would be a one and done purchase. As far as user interface, both Innuos and Aurender offers superlative Apps. I would give a slight advantage to Aurender Conductor App based on longevity, remote troubleshooting and excellent customer service.

@lalitk 

Thank you, and sorry …I was thinking of the N150 not the N100.

I believe that’s more in line with the new Pulse from Innuos.

It and the Pulse are both USB only and apparently that output is touted by both companies to be excellent ..and both are priced around the same ($3250 vs $3500)

I would say that would be my stretch at this point .  I can’t go to the N200 this year.

I love that the Pulse is sans screen but the N150 has a nice monochrome text only screen that is subtle and can be turned off.

So, my question is really… given that both those units are USB-only … would placing an Iris after them redundant or counter productive?

I will definitely look into a pre owned N10 based on your suggestion.

regarding the Ifi, it’s been a great intro to streaming.  I haven’t had to use the interface since I’ve been using Tidal Connect… but now I’m using Qobuz and I have to use the M-connect app to get the streamer to play those high rez files and I can’t stand using M-connect.

Thanks again 

@j_andrews 

RE: Iris, let your ears guide you if it yields improvements after Pulse or N150. BTW, Pulse has USB, coaxial, optical and AES/EBU outputs. 

@j_andrews My advice, especially since you’ve got an Iris, sell both your DACs and get a Musician Draco. Why? It’s got an i2S input that your Iris can provide to it. I’ve got an Iris feeding my Musician Pegasus into its i2S and the transformation over USB was at another level. Not even close. You want as short of an HDMI cable as possible, and I’m using this lowly 6” cable from Monoprice that was more than capable of showing the superiority of i2S. You’ve got a wonderful Iris, so I say USE IT!!! The Draco is 95% of my Pegasus (and by association the Denafrips Pontus ll) at a big discount, and it’ll love you feeding it with your Iris. Just my experience FWIW, and best of luck!

https://www.monoprice.com/product?p_id=13578

https://www.amazon.com/dp/B096S6HBQY/ref=syn_sd_onsite_desktop_30?ie=UTF8&psc=1&pd_rd_plhdr=t

 

Thanks for all the great suggestions 

happy new year!

@lalitk N200 is USB out with coax only for "legacy" or second system DACs. Which DACs in the =/< $5k range are specifically optimized for USB input? (External clocking is out of the question).

Maybe I don’t know what an ethernet based DAC is??? Isn’t it just converting the ethernet stream to a protocol like I2S? There isn’t a cable or a connector as it can be wired directly but wouldn’t it be prone to have all the same issues as a separate processor without the convivence of upgrading the source?

The Peachtree GaN 1 Beta eliminates the DAC by only accepting a COAX input but that’s not ethernet either???

Cheers

@hickamore 

Holo May KTE and Denafrips Terminator II are the two comes to mind at top of 5K range. Now I have not done head to head comparison with aforementioned DAC’s but did audition Konus Audio Digitale 2000 in a very high end system. Gorgeous analog sound with lots of detail. We listened to multiple genres and nothing sounded out of place or forced. The fact, Digitale 2000  - $3900 held its own in a system just shy of $100K, it was quite remarkable. My only knock, it does not do DSD or anything above 24bit/192kHz. 

Among the used bargains under $5K, take a look at SW1X Dac III, AQUA La Scala and Bricasti M3 DAC. They are currently listed at other site. 

@lalitk Appreciate the tips as ever and will check out those mentioned. Top two would be a stretch at present but Konus has my interest. I gather all are plausible candidates for USB-only streamers such as N200. Current DAC takes mini-USB only, which can't be ideal. 

Great discussion that has potentially answered why I have struggled with a streamer solution. It hasn't been for a lack of trying though. I've had several in my chain to date without experiencing a SQ improvement. I stopped the search last year and followed through with my original year long plan of buying new speakers. While saving for those I wanted a lesser bump with a better streamer than an iMac.

 

I currently use a SSD iMac (not a laptop, an iMac) and usb to a Holo Spring 3 KTE. This model and the May KTE have an optimized usb input that nulls power riding on the cable, is galvanically isolated, has good clock implementation, and nearly immeasurable jitter. 

 

The streamer I hoped would jump the SQ was an Aurender A10 borrowed from a neighbor. If the usb output from that older model is inferior to the Holo usb it is reasonable to conclude SQ would not improve?

 

If true, the question is at what point will I start experiencing better SQ from any streamer using usb out when feeding an already usb optimized DAC? There seems to be two camps designers are approaching streamers with. One is through usb and the other through I2S and some of the higher end lines offer both. Reading product data for the A200 I see there is an optimized usb out and equal design attention to implementing I2S with the statement it's a personal choice which to use without claiming either is better. How is it that better sound is achieved using a well designed usb in the A200 out to a DAC with usb that is already taking care of the known issues with usb? Optimize the optimized? Where is the improvement in this proposition. This is when my head explodes attempting to understand what is what and I give up in frustration. Worse is reading the many satisfied users here that figured this out and are enjoying the synergy of streamer/DAC.

 

I'm all for fitting this last puzzle piece and if it requires crossing the 5k line to get there it will take awhile to save up so I can trial.