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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 13 responses by djones51

djones51
4,947 posts
 
There are 2 reliable interfaces capable of transmitting DSD , ethernet and USB. If you're not interested then use optical, coax, or AES3. I2S was never intended for transfer between devices but on chip no more than an inch or two. There are a few DACs and streamers that have I2S just need to make sure what you're connecting to what is compatible. As far as jitter AES3 and coax will have more jitter than USB in well designed DACs. It's just the nature of the design, having the clock decided by the host like coax and AES3 causes more jitter than asynchronous transfer like USB. There's no puzzlement or spooky things at a distance bits are bits whether those bits are transferred by ethernet, USB, optical, coax or  AES3 it's the same bits.
djones51
4,947 posts
 
I click on my roon app, find an album and hit play. Nothing to worry about. I will add if you're going to use the approach of streaming it's a good idea to understand some basic networking and how digital transport works. Most of the stuff I read on digital threads about reclockers, line filters and cables is nonsense. I use a roon NUC connected to my network and a raspberry pi4 as a bridge to my DAC basic ethernet cat6 cable basic USB cable. Simple easy setup best sound I've ever had good as or better than CD and forget vinyl.
djones51
4,947 posts
 
Which music servers provide power over USB? 
djones51
4,947 posts
 
USB is already industry standard, sorry about that but no going back now. 
djones51
4,947 posts
 
@bilaltata
That’s similar to my experience. I’ve tried an Aurender, Benchmark DAC and a few others, I’ve noticed very little if any difference from a simple NUC running ROCK in my office and a little raspberry pi4 as a bridge connected USB to the Anthem. I’ve never found this problem some seem to have with USB. I think it’s more a case that USB used to be prone to jitter and sync issues but in asynchronous mode and isolation that most good DACs employ it’s not really a problem anymore. It's a case where people have been told for years USB isn't a good protocol for audio and years ago it had some merit,not now.
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. 
djones51
4,947 posts
 

Seems someone heard a difference
I'm glad they liked it. What I was trying to get across is using blanket statements like USB sucks because of 1 incompatibility without getting the manufacturer to help troubleshoot doesn't convey useful info. 
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. 
djones51
4,947 posts
 
There is a Audio Device Class for USB. 

The Audio Device Class Definition applies to all devices or functions embedded in composite devices that are used to manipulate audio, voice, and sound-related functionality. This includes both audio data (analog and digital) and the functionality that is used to directly control the audio environment, such as Volume and Tone Control. 

Don't fault the USB standard for manufacturers who fail to follow it or do so incompetently.
djones51
4,947 posts
 
If you're having problems try a Benchmark DAC3.


Benchmark's USB system supports USB Audio 2.0, DSD, and USB Audio 1.1. It is frequency agile, and will follow sample rate changes initiated by the computer and/or the media playback software. In all modes the USB communications are asynchronous in order to eliminate unnecessary sources of jitter.

The DAC3 has a low-jitter master clock which controls the transfer of audio data from the computer to the USB sub-system. The computer asynchronously transfers audio data to a buffer in the DAC3. The contents of the buffer are then asynchronously transferred to the D/A conversion subsystem. This second asynchronous transfer eliminates any traces of jitter that accumulate as the data is transferred between the USB and conversion subsystems. No traces of jitter-induced distortion are measurable to our measurement limits (better than -150 dBFS). This truly represents the state-of-the art. Enjoy the convenience of computer playback without compromise. The Asynchronous USB system supports USB Audio 2.0 for high-resolution 192kHz, and DSD playback. 

djones51
4,947 posts
 
It's  the title of the thread USB doesn't suck. USB might suck trying to connect incompatible components but that's not a fault of USB.

Care to highlight DACs that you consider to have superior USB implementation?


Well, any that work? I imagine the Antelope works great looks like nice DAC. It could be a little finicky in what’s connected to it.
djones51
4,947 posts
 
The market for USB clean up devices is there because people still believe USB is a problem interface from when adaptive or isynchronous transfer was used. Most all modern competent engineered DACs don’t use the clock sent any longer so what difference does it make how many times you reclock the signal before the DAC? Line noise isn’t a problem as the USB buffer in the DAC isolates it and it’s the firmware or software that translates the signal that interfaces with the DAC chip not the incoming line signal. Actually SPDIF will have more jitter than USB since it uses the clock from the source sent over the wire. As with anything that's product specific some DACs do better jobs. 
djones51
4,947 posts
 
If you build it.....they will come.

Maybe their stuff needs reclocking they didn’t build it right in the first place. Your DAC wouldn’t negotiate with a Zenith right? Buy one of these reclock things that will fix you up.
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