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All that "USB interface" audio noise. And better sounding USB via?

Justin Ayers

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USB has both power and data conductors in the same cable. That's where the issue comes from, not from the digital transmission itself.
I see. That explains things a lot.

This is, then, a case of audio equipment using a specification that wasn't designed for audio, simply because it's so cheap due to economy of scale.

Transferring the data to the playback unit and having that data transmission be stopped (rather than continuously streamed) should make it very easy to stop the noise, right? The interface would cut power to the cable and/or put up some other kind of 'complete stoppage roadblock' to prevent the noise from being present during playback.

Personally, I favor the localized storage model. Storage is so cheap now and so is RAM. Computers are also very cheap and tiny, those enough for audio playback. Not having to string cables around is an added benefit. Personally, I would use optical for very short cable runs (if necessary at all) and supplement it with as highly-localized-as-possible storage whenever possible. The only time analog would come into the picture is for use with passive speakers. Noise from non-audio spec conduits sending power and data together without being able to fully block noise via the basic minimal spec seems to be an easily-avoidable problem.

Eventually, the paradigm will be active speakers that have the files stored on flash (e.g. NVME) and which communicate with each other wirelessly for things like EQ (time synchronization, etc.) and volume. The only other external equipment will be the interface the listener uses to control playback. Even that might be mostly verbally directed, given AI improvements. Hand gestures in the air could also be used, if there is a camera. Transfer of files to the speakers' storage would be done wirelessly for convenience but playback would not happen via wireless streaming for quality and reliability reasons. All of the aforementioned is already possible, with reasonable cost requirements, today, too.
 
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mansr

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USB has both power and data conductors in the same cable. That's where the issue comes from, not from the digital transmission itself.
It's not that simple. If the power supply is noisy _and_ the DAC has poor filtering in its internal regulators, issues may arise regardless of which wires carry the power. The quality of the USB 5 V supply varies between computers/hubs, just like all power supplies can be good or bad. A poorly designed DAC can thus be sensitive to this whereas a good one is not. That's just half the story, though. Another, and I suspect more common, issue is ground-coupled noise. I have seen instances where a USB-attached DAC sounds fine with headphones, only to start producing horrible noises if connected to an amp. Similarly, the noise can depend on whether or not a laptop is connected to AC power. None of this has anything to do with the construction of USB cables.
 

abdo123

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This whole discussion is bullshit, just buy a DAC that measures well with its USB input on this forum (there are dozens).

I’m not trying to be rude but if there is a problem these DACs fixed it, lets move on ffs.
 
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