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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

Showing 4 responses by redlenses03

redlenses03
101 posts
 
USB for a DAC??? Never.
I guess you realize that dogmatic statements like this without any context and nothing to back them up are basically worthless and add nothing to the conversation?
For the most part, but people like what they like and are free to do so, nothing wrong with that. 

This thread has basically dissolved itself.  To say "X" interface is __ means nothing without context and shows a typical follower knee jerk reaction to what others say.  This hobby has sooo much of this pile on mentality. 

Although, it isn't (and shouldn't be) a requirement to have an engineering degree to enjoy / understand every piece of gear.  However, short of being a plug and play person (which is totally fine), if one chooses to get a bit more into the technical side of things, it behooves the individual to research AND experiment to get a better understanding of whats going on and to determine what best fits THEIR environment /setup

Every product is different and usually has one or two interfaces that work best from the design intent (many have significant differences) - its not really that hard to understand or accept.
redlenses03
101 posts
 
A lot of misinformation being spun here.  I think the title of the thread pretty much sums up the irrationality in so far as a sweeping generalization.  If I said McIntosh sucks, I suppose it would be due to my personal experience which is certainly valid as is the OP's umm, OP. 

Certainly if I was struggling with a certain technology with my gear it would be frustrating, I totally get it.  However, the time that USB has been around and matured is very evident and in many cases surpassed most other interfaces. That's not to say it doesn't have issues.  I think one has to approach such statements with some maturity and understanding of the technology.  There isn't one "connection" type that exists that someone at some point hasn't had an issue with their gear. 

If the designer and the implicit design intent is focused entirely on USB, or opt, or spdif, or Ethernet etc....chances are THAT interface will acell above any other in that particular product.  Its actually very apparent in numerous products and nowadays, USB pretty much dominates most product interfaces. 

Creating a really GOOD Ethernet interface in a DAC is very expensive.  The same goes for pretty much all other types > USB, i2s, opt etc... .  Sure you can load up a component with everything under the sun, but it's THE IMPLEMENTATION of said interface that matters.  This has been stated ad nauseam throughout most forums.  My .02



redlenses03
101 posts
 
Far from having ‘dissolved itself‘ I sincerely hope that this thread might lead serious designers to reconsider whether rather than using a low end, convenience consumer interface with all its known foibles to transmit high quality audio, one might usefully revisit more appropriate formats (optical, I2S, AES/EBU) to improve on what is at best an unacceptably wide range of outcomes with USB; I also note with a degree of puzzlement that members of the ‘bits are bits’ school of sitting on your ears are alive and well

Respectfully, it kinda has.  Its' just another "I'm right you're wrong" (not directed at you).  Armchair experts everywhere.

Its fine to not like USB, or.......but keep in mind it's an individual use case.  This thread isn't going to change a designers mind to all of a sudden say, "hmm someone on the web doesn't like USB, I should probably use spdif"
The amount of info with issues, aka " with all its known foibles" on every interface is easily documented / found.  i2s, AES etc.. ALL have (potential) issues/shortcomings, given how its implemented in certain products.  It's either done right or not.  Again, implementation has been repeated ad nauseam.  That's the bottom line on how I see it.

I'm not trying to change anyone's mind, why would I care, whatever floats your boat.   Everyone's use case (which is pretty critical in the overall scheme of things) is different and It's really about having a mature discussion. 


redlenses03
101 posts
 
...........As well as tons of variability in implemented Ethernet connections or eth cables, i2s, spdif, tos...etc...  
Because a product and or more importantly, a specific use case has an issue, doesn't fault a connection type in the broad spectrum.  Far from it. 

With all that has been learned and the advancement in USB, if its well implemented, its probably going to be the better connection in said device.
Will Ethernet connection (or maybe better yet fiber sfp) be the standard?  Maybe and that would be great.  However, there aren't many GREAT Ethernet DAC's available though as compared to USB. 
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