USB cables - the good, the bad and the ugly

I completely concur that cables won’t make a system, but can be the final, small tuning step. I have, however, had some moderately expensive (high 3 - low 4 figures USD) cables break my system (as compared to a 2 figure cable expenditure). Fortunately, those were on loan from a dealer, so back they went with no harm to me.

Cheers!

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I admire your verve but I fear you are seriously wasting your time with the likes of the bits are bits fraction.
Don’t feed the troll :roll_eyes:

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I know…but the “bits are bits” and “digital cables are all the same” factions conveniently forget that the digital data are moved around in what is effectively an analog envelope.

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But surely the analog signals of 1 and 0 are not altered?

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It’s not a matter of “conveniently forgetting” this truism, it’s rather a matter of understanding its significance.

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As a great man once said:

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Well said @hmack - this seems to be the Roon version of trolling: anybody who doesn’t believe in something piles in with, effectively, abuse. Shame.

No, I’m just trying to stop the weird semi religious, flat earth style nonsense which is believing digital cables bear any significance to sound quality.

I’m sure back in the dark ages they were quite happy burning midwives and curing a missing Leg with leeches. They probably thought they were right too. But like the cable debate, there’s absolutely zero evidence that any cable which meets the required standard has any effect on sound quality whatsoever.

I think the trolling is more on the part of those happy to believe in myths, legends and subjective hearsay.

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This comment is brought up frequently, but while it is true it is not relevant.
This is about levels of abstraction.
If you want to look at the lower levels of abstraction, you could just as well say that the analog envelope is really transported at a grainy level by individual electrons, and it isn’t really grainy because quantum mechanics tells us that the electron is really a smeared-out probability wave. All true, but not relevant.

And between the signal and then align envelope you have the routing of the IP layer that does not guarantee that packets arrive in the proper order so the ordering has to be restored by the recipient network stack.

The system is designed so that the lower levels of abstraction do not matter, which is the reason we can transport the music over Ethernet and WiFi and cellular and across the Atlantic: with these different implementations at the lower levels, the higher levels stay the same.

So the analog envelope has no impact on the signal. It is invisible to the algorithms.

Now, you could make an argument that the physical implementations have side effects such as transmitting noise. That may or may not be true, and if true it could be mitigated by different techniques. But that is different from the analog envelope argument,

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No sir! You are trying to justify the fact that you cannot discern differences between digital cables. The reason for this might be one of several reasons, you are an inexperienced listener, the material might not be suitable for comparisons or perhaps that you are suffering from a nocebo effect since you cannot grasp the technical and/or physical reasons to why this might ne happening.
Whatever reason, you can stop lecturing now.

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LOL! That is all.

I admire your verve but I fear you are seriously wasting your time :wink:

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Who’s lecturing whom, dude?

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I have always wondered why it is professional audio reviewers will say they can hear a noticeable difference between cable A and B, but when asked to do a Blind AB test, they instantly refuse to do it.
I wonder why?

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Because everyone hears differently despite what they might think.

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Maybe, but I am more likely to suspect that in a blind comparison, their accuracy to choose cables apart from each other ends up relying more on random chance than discernible differences.

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You are comparing apple to oranges.

I am not talking about networking here. I am talking directly connecting the Roon Core to the DAC via USB which is a much different animal. I have already commented in other places that using Ethernet with a Roon Core/Roon Endpoint model is a great way to isolate the DAC from a noisy Roon Core.

With the Roon Core directly connected to the DAC using USB, my comment is quite relevant, thank you.

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Maybe tangentially relevant, but not precise. I doubt that you have an electrical engineering level understanding of signals, Scott. Because as AndersVinberg points out, your terminology is off kilter.

“Analog envelope” refers to the bounds of an analog carrier (MHz, GHz), which in this case then is digitally modulated (FSK, QAM). If the analog carrier itself is the source of perceived noise after digital demodulation, then there is no hope for improvement. Filtering out the analog carrier concomitantly would remove the digitally modulated signal. Radio silence. No analog carrier, no digital signal.

So, what you really mean is electromagnetic interference. That is not part of the analog carrier. It is extraneous noise, and if that noise is out of band, then it likely can be filtered out with little effect on the analog carrier and digitally modulated signal. Whether significant electromagnetic interference is present or whether it needs to be filtered is debatable. But test bench measurements generally can answer that question.

AJ

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I was speaking about both because the analog envelope comment is often used for both.
And my objection stands.
The layers of abstraction apply.

This description applies to both:
They send packets of information: the sender takes a certain amount of information and puts it in a packet, which is equivalent to writing it on a slip of paper.
This packet is then sent over a transport stack, which differs between the two technologies, but at the bottom it is transmitted as bits, which are actually analog electrical signals, which are actually electrons, which are actually quantum wave.
At the receiving end, the network stack (hardware and software) collects these signals, decodes them, and when it has the complete packet it taps the application layer code on the shoulder and says “I’ve got some information for you, give me a buffer to put it in, this size”. The app allocated a buffer which is also like a piece of paper and provides it. The OS copied the information from one piece of paper, and the application reads the numbers from its piece of paper, decodes them, and presents them to the DAC with appropriate timing information.

So how does the analog envelope of the USB signal have anything to do with this? Any more than the composition of the paper fibers, if we actually used paper?

The analog envelope, if it gets distorted, affects the timing of the signals that are transmitted at the bottom layers, but that has nothing to do with the timing or other attributes when the app reads the numbers out of its own buffer, or when it presents the numbers to the digital-to-analog circuitry.

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And the CDs I buy also are shipped in an analog envelope. You will say the envelope will make any difference in the SQ of the shipped CD? What envelope is the best for shipping CDs to have perfect SQ?