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USB sucks

USB really isn‘t the right connection between DAC and Server: depending on cables used, you get very different sound quality if the server manages to recognise the DAC at all. Some time ago I replaced my highly tuned Mac Mini (by now-defunct Mach2mini, running Puremusic via USB) with an Innuos Zenith Mk3. For starters I couldn‘t get the DAC (Antelope Zodiac Gold) and server to recognise each other, transmission from the server under USB2.0 wasn‘t possible because the server is Linux based (mind, both alledgedly support the USB2.0 standard) and when I finally got them to talk to each other (by using Artisansilvercables (pure silver) the sound quality was ho-hum. While I understand the conceptual attraction to have the master clock near the converter under asynchronous USB, the connection‘s vagaries (need for exact 90 Ohms impedance, proneness to IFR interference, need to properly shield the 5v power line, short cable runs) makes one wonder, why one wouldn‘t do better to update I2S or S/PDIF or at the higher end use AES/EBU. After more than 20 years of digital playback, the wide variety of outcomes from minor changes seems unacceptable.

Since then and after a lot of playing around I have replaced the silver cables by Uptone USPCB rigid connectors, inserted an Intona Isolator 2.0 and Schiit EITR converting USB to S/PDIF. Connection to the DAC is via Acoustic Revive DSIX powered by a Kingrex LPS.

The amount of back and forth to make all this work is mindboggling, depending on choice of USB cables (with and without separate 5V connection, short, thick and God-knows what else) is hard to believe for something called a standard interface and the differences in sound quality make any review of USB products arbitrary verging on meaningless.

Obviously S/PDIF gives you no native PCM or DSD but, hey, most recordings still are redbook, anyway.
Conversely it is plug and play although quality of the cable still matters but finally it got me the sound quality I was looking for. It may not be the future but nor should USB, given all the shortcomings. Why is the industry promoting a standard that clearly isn‘t fit for purpose?

Finally, I invite the Bits-are-bits naysayers to go on a similar journey, it just might prove to be educational.
antigrunge2
erik_squires
15,826 posts
 
USB / Linux support is tricky.  Sadly Linux is not as easy to add DAC drivers to compared to Windows or OS X, but since so many streamers are Linux under the covers this is often a high priority target.  As I remember, Linux requires the DAC drivers to be compiled with the kernel, so it was never as easy as dropping a file or changing a config setting. 

It took Ubuntu from version 16 to 18 to have my Mytek USB chips baked in.

However, I would never do anything else.  High speed USB can provide all speeds available of DSD and PCM.
djones51
4,947 posts
 
Mine journey was very educational. I connect a raspberry pi4 running Ropiee as a Roon bridge  to an Anthem STR integrated with a basic USB cable and it works like a charm and was easy to set up. The trick is knowing what works with what and bypassing all the idiotic useless isolators, reclockers , expensive  cables and other such stuff. Knowing which DACs have excellent USB implementation also works wonders in the digital world. 
davide256's avatar
davide256
395 posts
 
I like the Zen Mk III, its one of the few servers that I have heard sound consistently good at CAF. In my NUC server solution the USPCB  and Eitr have been retired, I use a Lush 2 with an Audiophonics USB-B Adapter Cable for DC Power Supply and an LPS 1.2 for USB 5v to USB DAC.  Overall I find that the downstream USB receiver in the DAC is impacted by even minuscule voltage noise from the upstream device and the DAC's power supply quality.
antigrunge2 OP
1,346 posts
 
@djones51The Antelope Dacs are not known to be slouches in the USB department. The superiority of the S/PDiF solution I now use is though substantial. Care to highlight DACs that you consider to have superior USB implementation?

motokokusanagi
189 posts
 
@antigrunge2 Your listing of a 5-box-dongle-device-doodad-decrappifier chain made me chuckle as we’ve all been there.

Every single audio component that there has been is subject to the most mindwracking-OCD-FUD optimizations (cable lifters, anyone?), but none can rival USB for the sheer number of them!

How has it become not even viewed as a red flag when the cost of baseline connectivity can easily exceed that of the audio emitting component itself! I’m talking the DCS Network Bridge, Berkeley Alpha USB, Innuos Phoenix, Aqua LinQ (just found out about that one), SotM horde of unpronouncables, the entire Uptone and Pink Faun product catalogs, the majority of iFI’s digital accessories, and bizarro cottage industry of power supplies. Rather, why are the problems these products claim to solve not addressed in the audio components themselves!

Do all those Macminis straight into the first asynchronous DACs sound like crap now? Or did they then?

And then there’s the cables.
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