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A nearly perfect USB cable tester

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81–90 of 181 posts

Re: A nearly perfect USB cable tester

#81
post #62

What I'm looking for is a differential signal tester, where you can breakout any arbitrary cable or traces and test the properties of the wire with different frequencies. It should be able to measure interesting properties such as resistance, capacitance, inductance, phase/length difference, wire length, etc. One of these devices for approximately $100 would sell all day long.

You can do that with a nanoVNA, except for the differential part. Less than $100.

Re: A nearly perfect USB cable tester

#82
post #70

Earlier quoted context omitted.

The reason it is thick is because it supports 65W charging. Apple did the same with the USB-C cables that shipped with the pre-MagSafe MacBooks. It was a thicker cable that supported 100w charging but was only USB 2.0.

Can you help me understand why that would be a reason to compromise the comfort of the cable that is supplied for a device which charges at 5w? Or, why Apple manages the same in half the footprint? Or, why someone would expect that a cable that came with a pair of headphones actually charges things at over 65w?

Like most things in the audiophile world, it's more about aesthetics than anything else. A big cable looks like it means business.

Re: A nearly perfect USB cable tester

#83
post #80

Earlier quoted context omitted.

“I don’t think..” Ok, you’ve made a number of assumptions and we don’t share the same priors so I’m unable to follow you to your conclusion. I think you are underestimating the importance of perceived premium combined with the pressures of cost accounting, but I do think that is pretty normal for ‘audiophiles’ which is their target market.

Which assumptions? The weight reduction on the S2 is documented and the cable’s 65W rating is what the tester confirmed. If the argument is that B&W deliberately chose a thick cable to seem premium, it doesn’t square with them actively slimming down the headphones. B&W are primarily a speaker company, their USB-C product range is basically just a few headphones and earbuds. More likely they just sourced a generic cab…

My point on weight was that the market for that it is common, which is probably a stronger statement than needed. I should have made the weaker argument and said the market exists which only needs one example. The company Beats can serve as that example, this company sells the majority of premium headphones but I don’t actually know what percentage have weights placed in them. I am assuming a non trivial percentage.

You are using circular reasoning in your logic, you assume the premise is true and from there you derive your evidence.

I would contend that someone thought about it and decided to go with the cheaper option because they could get away with it. I would consider my assumption to have more grounding given my experience with manufacturing and cost accounting.

Re: A nearly perfect USB cable tester

#84
post #35

As someone who really doesn't care about learning the details, and just want one USB-C cable that does it ALL to put in my backpack what should I buy ?

I’m sure it’s overkill but I wanted to know how much power my laptop or whatever was actually drawing. https://iaohi.com/products/aohi-the-future-adonis-usb4-2-0-2...

As an alternative, you could get a stand-alone USB-C power meter which can be used with any cable. That way, when the cable breaks, you don't have to buy a new power meter. Here is an example of one such product (though I've never used this model): https://www.amazon.com/Adapter-Voltage-Current-Extension-Con...

Re: A nearly perfect USB cable tester

#85
post #59

I actually purchased one of these as this article has surfaced before. It’s well worth the hype, I used it to audit all my cables (both for home and work) and it’s amazing how many thick and unwieldy cables are actually terrible for data. For example I purchased a pair of B&W Px8 S2 noise cancelling headphones, which boast a DAC if you connect via USB-C directly, the cable it came with though was thick but only rated…

> so shipping with a chunky cable that doesn’t even carry decent data feels like a bizarre oversight.

USB 2.0 can support up to 480 Mbps. It’s more than fast enough for any audio stream you can send to a DAC.

Your headphones don’t need USB 3.0 5 Gbps speeds. USB 3 requires extra wires with different properties that need to be controlled more tightly, which can impact cable flexibility. If your headphones used USB 3 when they didn’t need it that would be one more thing to break and more failure modes for the cable.

A USB 2 cable with fewer conductors was the right choice for this product. The fact that you only got miffed about it when plugging the cable into a tester, not from actually using the product or cable, is good evidence that a USB 3 cable wasn’t needed.

Re: A nearly perfect USB cable tester

#86
post #80

Earlier quoted context omitted.

Which assumptions? The weight reduction on the S2 is documented and the cable’s 65W rating is what the tester confirmed. If the argument is that B&W deliberately chose a thick cable to seem premium, it doesn’t square with them actively slimming down the headphones. B&W are primarily a speaker company, their USB-C product range is basically just a few headphones and earbuds. More likely they just sourced a generic cab…

My point on weight was that the market for that it is common, which is probably a stronger statement than needed. I should have made the weaker argument and said the market exists which only needs one example. The company Beats can serve as that example, this company sells the majority of premium headphones but I don’t actually know what percentage have weights placed in them. I am assuming a non trivial percentage.…

You’ve gone from “companies add weight to feel premium” to “they went with the cheaper option because they could get away with it.” Those are opposite explanations. But either way, the cable doesn’t do what its physical presence suggests, nothing on it tells you otherwise, and that’s the entire point of the device in the article.

Re: A nearly perfect USB cable tester

#87
post #66
post #61

Earlier quoted context omitted.

Is there any audio you might play that doesn't fit in 400Mbps?

The point isn’t really about audio bandwidth; it’s about the cable being strangely overbuilt for what it actually does. It’s rigid and thick, like a Thunderbolt 3 cable, yet only supports USB 2.0 speeds and fast charging for a device that doesn’t need fast charging. Compare that to Apple’s iPhone USB-C cable which is thin, flexible, and supports the same features. That matters because someone might grab that cable as…

> The point isn’t really about audio bandwidth; it’s about the cable being strangely overbuilt for what it actually does.

The purpose of the heavy construction is to make it durable, not to carry 5 Gbps data streams to your headphones.

Unlike most USB peripherals like your printer and keyboard that get plugged in and then don’t move around, headphone cables go to your head and move around constantly. They can get pinched in drawers or snagged on corners.

Hence the more durable construction.

Re: A nearly perfect USB cable tester

#88
post #3

The thing that has been bothering me for a while is that the USB spec allows for software detection of capabilities. You can read the emarker data and see the supported protocols, speeds, voltages, etc. But there is not standard for usb controllers to present this data to the OS. So it’s stuck in the low level firmware and never passed up. In theory we could have a popup box that tells you that both your computer and…

Perhaps someday it will earn the same level of importance as charging; iOS 26 calls out slow chargers on their iPhones, so you can run to the Apple Store and buy a fast one!

They probably have to weigh potential new hardware sales against added complexity. I have counterpoints too but: I believe they try to protect users’ mental models of their ecosystem (which perhaps I appreciate when I don’t notice, and can’t stand when something is uncustomizable). Like there are enough variables they don’t trust us with as it is.

Re: A nearly perfect USB cable tester

#89
post #86

Earlier quoted context omitted.

My point on weight was that the market for that it is common, which is probably a stronger statement than needed. I should have made the weaker argument and said the market exists which only needs one example. The company Beats can serve as that example, this company sells the majority of premium headphones but I don’t actually know what percentage have weights placed in them. I am assuming a non trivial percentage.…

You’ve gone from “companies add weight to feel premium” to “they went with the cheaper option because they could get away with it.” Those are opposite explanations. But either way, the cable doesn’t do what its physical presence suggests, nothing on it tells you otherwise, and that’s the entire point of the device in the article.

My position is entirely consistent, it is cheaper to signal premium quality than actually deliver it. The point I am making is that there is immense comercial pressure to do this is a highly competitive market when selling to consumers who don’t know better.

My example of weights is that the steel weighs are cheaper than the alternative of using heavier drivers, by adding weight they are signaling premium without delivering it. Similarly with the USB cable, consumers assume such cables are thick because of thicker wires and better shielding, it’s cheaper to make a thick cable without those those features, once again signaling premium without actually providing it.

Re: A nearly perfect USB cable tester

#90
post #35

As someone who really doesn't care about learning the details, and just want one USB-C cable that does it ALL to put in my backpack what should I buy ?

LTT did a lot of work to prove their cables do everything they say:

https://news.ycombinator.com/item?id=47561827

(these are what I would buy from a sea of cables, not the cheapest, but far from the most expensive)

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