Theoretical arguments are not in themselves convincing. Audio forums are replete them.
You really haven’t answered the query I posed: If as you pose there is substantial sound degradation with unfiltered USB, short of corrective measures, such as the FMJ, why aren’t and haven’t audiophile level cable, streamer and dac developers been talking about dealing with it as absolutely necessary and providing solutions? Has there been a conspiracy of silence, incompetence, or what all this time? Even AQ, centrally a cable company, took years to come out with the FMJ. Yet, it’s posted as an accessory, not a necessary element of using their USB cables.
Whatever the value of filtering – I don’t have an opinion – something doesn’t add up in the insistence of your claim (and the examples provided in the articles you linked).
The problem is directly proportional to the DCR RF ground differential, that’s why it was stated as such. You seem to want to adopt the hersey and not the proven facts, or even read the papers that educate you on the problems. Your choice, I’ve gone out of my way to help you with the physics that is reproducable and factually correct, ALWAYS and ALL the TIME. DCR between grounds is a fact of electronic life.
YOUR system ground network is at fault for external ground differential, not the devices that are designed to an ohmic tolerance on most grounds. There is no conspiracy. You have adequate ground or you don’t. RF, not being audible, can be tricky to pinpoint in BER excursions. A simple isolation device for mere pennies on a audiophile’s budget can put that to rest.
You don’t want an answer. There is nothing that doesn’t add up in the insistence of my “claims” because they are not a claim, they are the facts. But you’ll side with heresay? Again, the magnitude of the ground ground differential define when we hear it and call it a ground loop. The two articles that I can easily deduce you didn’t read show the problem in tests very plainly. This is not a liberal argument. Science just isn’t. It can be currently unquantified at times, but until the physics is valued in measurement, it is there to be found and never changes it’s spots just because we haven’t defined a test yet. In this case, we certainly have.
The problem is as easy as the factual DCR of a wire. Got any with no resistance? Most ground loops are below audability in a proper ground system.
This isn’t theoretical, it has been PROVEN and CONSISTENT. Grounds are not all at the same potential to a reference, it is impossible.
Wrong. They say that IMPROVEMENTS that are well defined and repeatable are just too good to be heard. Not the same thing at all. “We” say that done well and thorough enough in a resolving system they do improve things. The science of cables done right are measurable. We need to move on from ignoring that.
If you’ve decided that Fred and Rob at Lampizator NA are who you choose to believe then just buy a streamer with a USB output that fits your needs and an appropriate USB cable and be done. A safe starting point would be the same coax cable you like in USB. I’m partial to the Inakustik Reference or the Tubulus Concentus. Continuing down the current discussion path is pointless.
If you read my post, the challenge is general, not just Lampi, although Lampi would have all the interest in the world in saying something. It’s not like USB is some esoteric option few would consider. Where are the developers who are informing customers of the problem? PS Audio?
Academics and many other engineers claim cables don’t make a difference on theoretical and scientific grounds. Until they listen — with an open mind. The distinction I’m making is between the theoretical and practical applications, about the evidence for the latter in high end gear. I say again, I have no basis yet for an opinion (I’m soon to hopefully find out more). Thus, short of that, as a scientific thinker, I’m looking for corroborating circumstantial evidence of an empirical kind that one would expect to find were USB a common problem, or at least a substantial one, with the level of components discussed in forums like this.
USB isn’t a common problem. I get the idea you feel the problem has to be endemnic to the technology. It isn’t. It is a problem when ground differential is too high and that can be mitigated. It exists because of the ground path DCR.
Claims are meaningless to me. A verbal claim is an unproven hypothesis and the beginning of the scientific process, not the end of the process (a real and unbiased repeatable confirmation). In God we trust all else bring the data.
Analog and digital cables do measure differently in many ways, and all to accepted measurement methods. If someone wants to trial and decide that a cheaper cable is good enough for them…no problem. That doesn’t all of a sudden erase the differences between cables.