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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
djones51
4,947 posts
 
I've used spdif, optical, usb. They have all been plug and play. Using Benchmark, Topping, Micromega, Anthem, NUCs, raspberry pi4, MiniDSP SHD, Aurender and a few others. I already gave the comparison I notice very little is any difference other than USB does higher rates. I don't know about Antelope products but on their website for the Platinum Model it says
Hi Speed USB (480 Mbits). Zodiac Platinum uses USB connector Type B and operates up to 384 kHz sample rate with Mac and PC ASIO drivers.
The zenith is Linux based and I agree it should work but I have read where some have had problems. The first response to your thread a problem was mentioned with a Mytek product and Linux. Of those I mentioned MiniDSP, Aurender, the NUC and raspberry pi are all Linux based and I never had any problems.  SPDIF is an old protocol and it works on basically everything, if you don't need or want higher resolution then no problem. But you're claiming USB sucks based on one incompatibility and you never mentioned if you contacted the manufacturers of either product to trouble shoot.  You're entitled to your opinion that USB sucks. To me it's the only interface I use for superior audio transmission. 
dougeyjones's avatar
dougeyjones
163 posts
 
People in here claiming that USB sucks should really read some DAC reviews over on the much maligned AudioScienceReview, who fastidiously measure all outputs when conducting DAC/Streamer reviews. Coax and Toslink are routinely trounced by USB in terms of absolute noise floor.

All the talk about 5v USB line noise on these forums seems to exist mostly free of evidence/proof.
antigrunge2 OP
1,417 posts
 
@dougeyjones,

as you are so assertive on your view: why is there a significant market for USB clean up and reclocking devices by Uptone, Intona,IFi, Schiit, Berkeley Alpha, InnuOs, Aqua, DCS et al?Are they all selling snake oil? Or are they maybe onto something after all?
Listen and enjoy
jaytor's avatar
jaytor
765 posts
 
Of the various inputs supported by DACs on the market today (SPDIF, AES3, Optical, I2S, USB, Ethernet), only USB and Ethernet provide an asynchronous input.

Using an interface that requires the clock signal to be generated by an eternal device (server, streamer, reclocker, etc.) and then pass that over a cable with connectors (which even in the best case will have impedance irregularities causing reflections) makes no sense with today's technology. The DAC needs to be responsible for the clock in order to minimize jitter. 

Ethernet might ultimately be a better electrical interface than USB, but until the industry standardizes on a single, simple protocol over Ethernet, USB is our best option. 

I'm sure there are otherwise good DACs that don't do a very good job with USB, but that is changing. With the rapid increase in popularity of streaming, most DAC vendors are recognizing the importance of USB as an interface, and I think it won't be long before this is the preferred interface for most users.
dougeyjones's avatar
dougeyjones
163 posts
 
@Antigrunge

I’m assertive in my opinion because it’s borne out by evidence derived from testing. The reclocking and cleaning products you refer to have been shown to do more harm than good on numerous occasions if you’re referring to USB.

Example:

https://www.audiosciencereview.com/forum/index.php?threads/ifi-micro-iusb3-0-usb-filter-review.11284...

The conclusion really says it all.
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