USBphoolery Nordost Valhalla 2 Type A to Type B USB2 Cable £3230 1m - Page 1
Forum section: electronics / general

author: MrMobodies
author_rank: Super Contributor
timestamp: April 22, 2021, 01:39:45 pm
content: Looks like they are now targetting USB cables.https://www.futureshop.co.uk/nordost-valhalla-2-type-a-to-type-b-usb-cableQuote*These cables are only specifically designed to work with stupid naive British suckers as they are of higher value to us and are more wanted than anyone else in the world.Thick USB3 cables and beyond are out there and yet they aim for USB2.I was interested in this: Velocity of Propagation: 90%What is that suppose to mean?https://www.everythingrf.com/community/what-is-propagation-velocity-in-a-cableQuoteSo that is used for coax cable but I am not seeing how that USB2 is coax.Am I missing something?What do you think?

author: magic
author_rank: Super Contributor
timestamp: April 22, 2021, 03:33:53 pm
content: It means that signal propagates through the cable at 90% of speed of light. Or so they say, but that would be easy enough to measure with a scope if you don't mind buying one for science.But I am a little concerned about their marketing, because the nanoseconds of latency gained that way will not translate to a dramatic improvement in transfer speed.

author: fourfathom
author_rank: Super Contributor
timestamp: April 22, 2021, 04:13:32 pm
content: Quote from: MrMobodies on April 22, 2021, 01:39:45 pmAs magic said, it's the propagation speed. All cables, wires, traces, etc. have a velocity factor, not just coax. The value depends on the dielectric, be it plastic, air, or vacuum.When I worked with communications networking fiber optics, I found it interesting that the velocity factor of optical fiber is generally lower (slower) than with the old twisted-pair phone lines (a combination of plastic and air dielectric). Not by a lot, and of course the fiber has hugely more bandwidth than copper, but the signals do get there more quickly with copper.

author: ConKbot
author_rank: Super Contributor
timestamp: April 22, 2021, 09:42:45 pm
content: The velocity factor there is total rubbish. You won't start breaking above 75% until you start using foamed dielectrics. Even air dielectric coax (https://www.tessco.com/product/4-heliax-standard-air-dielectric-cable-587956) is barely breaking into the 90's.Also 7 nines copper seems extremely dubious. And not twisting your pair isnt helpful for noise rejection since EMI coming from one side couples into one wire more thn the other. It's in a foil/braid overall shield, so probably not going to be bad enough to make a USB 2 link fail.

author: srb1954
author_rank: Super Contributor
timestamp: April 22, 2021, 09:53:47 pm
content: They didn't say anything about the wooden sleeves on the cable!You would ordinarily expect them to serve up a whole page of marketing BS on the the special qualities of the wood used in these sleeves and how it enhances the listening experience.

author: Humanoid
author_rank: Regular Contributor
timestamp: April 23, 2021, 06:49:51 pm
content: Just what a needed. A $3k USB 2 cable for my Power Mac G4.

author: Ben321
author_rank: Frequent Contributor
timestamp: April 24, 2021, 10:26:39 pm
content: Avoiding use of a twisted pair, and instead using several parallel wires, will allow the same length of wire to be used in a cable that's a couple inches longer, if the cable is already several feet long. It's not that much of an improvement. It's a tiny fraction of its overall length. It's not a very tight twist that's being used in most cables.It's not a significant improvement over a normal cable. But it also isn't bad. It doesn't add a lot of RF noise to the cable (somebody here claimed it would), as it's already not a very tight twist in even normal cables. And anything additional RF noise would easily be blocked by the per-wire shielding they added. Each of the 4 wires has itself become effectively a coaxial cable, by them adding a braided shield around each of the 4 wires in the USB cable.The only part I don't like is the fact they are charging thousands of dollars for these cables. That price make it seem far more like a scam than any of their claims they made about its effectiveness. There's no way that any USB cable would ever be worth that much money.

author: magic
author_rank: Super Contributor
timestamp: April 25, 2021, 06:37:36 am
content: I think most customers pay for the last feature: elevation of digital streaming to reference quality

author: fourfathom
author_rank: Super Contributor
timestamp: April 25, 2021, 02:53:41 pm
content: Quote from: Ben321 on April 24, 2021, 10:26:39 pmThe twist is more to establish the impedance of the balanced pair, and the tightness of the twist only makes a difference in common-mode interference balance in very near-field situations. It's the balanced pair versus single-ended configuration that makes the big difference. I have no idea how much common-mode rejection the typical USB receiver has, so perhaps twin coax cables might be better as they will have less common-mode than poorly-shielded twisted pair.And of course none of this makes the slightest difference in audio quality. It probably also makes zero difference in the digital quality (BER).

author: Daixiwen
author_rank: Frequent Contributor
timestamp: April 26, 2021, 07:38:15 am
content: Quote from: srb1954 on April 22, 2021, 09:53:47 pmI was a bit disappointed by this also. Those are wooden ferrites. Metallic ferrites negatively affect the audio signal, reducing spatial directivity and dynamic transients. Wood is better. Wood is always better, if we could use conductive wood we'd make cables out of them.

author: Haenk
author_rank: Super Contributor
timestamp: April 26, 2021, 01:00:37 pm
content: Call me nitpicky, but a licensed (certified) USB-product needs an USB-logo (and stuff) on a "flag-type" sticker attached to the cable.

author: robca
author_rank: Frequent Contributor
timestamp: April 26, 2021, 06:52:06 pm
content: Audiosciencereview has many times before tested high end USB cables, and usually found them just the same as cheap cables of the same length, debunking all the audiophool claimsThere has been one cable, though, which against all expectations did have (marginally) better measurementshttps://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-wireworld-starlight-7-usb-cable.6599/.And, yes, none of those improvements were audible, but it's the first time I see an actual effect from a USB cable, when measured by a reputable source

author: magic
author_rank: Super Contributor
timestamp: April 26, 2021, 08:05:27 pm
content: That's just noise pickup, but what about propagation velocity and packet latency, impedance matching and uniformity, high frequency attenuation and rounding of digital square wave corners, et cetera, et cetera?Given all the hair splitting between 0.1ppm and 0.2ppm THD headphone amplifiers, I hoped for a better review from that guy

author: Stuart Coyle
author_rank: Contributor
timestamp: April 26, 2021, 09:10:01 pm
content: The wooden sleeves have the grain going the wrong way. You'd get much better clarity and transparency in the woodwind section if the grain was going the other way. Otherwise, these seem like very nice cables, it's a pity I can't afford them.