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A nearly perfect USB cable tester

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Re: A nearly perfect USB cable tester

#21

Post by fmajid »

scq wrote: post #18
jmalicki wrote: post #14

Earlier quoted context omitted.

So you're saying there is something to audiophile grade HDMI cables?

No. What it can affect though is the bandwidth of the cable, meaning e.g. for HDMI cables, they might not support higher resolutions or framerates. If it's on the border you might see random disconnects or screen blanks. The quality degrading is not something you will see, as it's a digital protocol. "Audiophile grade" HDMI cables are likely to just be a Shenzhen bargain-bin special with some fancy looking sheathing…

Indeed. If I want super high quality cables, I get them from Blue Jeans Cables, who tell you exactly what Belsen or Can are cable stock and what connectors, as well as the assembly methodology.

Re: A nearly perfect USB cable tester

#22

Post by wolfi1 »

Onavo wrote: post #11
wolfi1 wrote: post #5

Earlier quoted context omitted.

there are several: one that is moderately priced and which I consider myself to buy is the JOY-IT UM120

Thanks, why do you prefer that particular model?

I wanted to have a model which tells me the modes which are supported and which is actually selected for a reasonable price and which I can order at a reasonable trader. this model seems to do the trick

Re: A nearly perfect USB cable tester

#24

Post by jmalicki »

HPsquared wrote: post #17
jmalicki wrote: post #14

Earlier quoted context omitted.

So you're saying there is something to audiophile grade HDMI cables?

With digital signals and ECC, the cable need only be "good enough" to get perfect data transfer through the system.

His link made very clear the issues of jitter and flickering.

Re: A nearly perfect USB cable tester

#25

Post by jmalicki »

atoav wrote: post #19
jmalicki wrote: post #14

Earlier quoted context omitted.

So you're saying there is something to audiophile grade HDMI cables?

No. What I am saying is that it is hard to test the quality of a 8K 240Hz 4444 video cable without having a device that can send and receive this or even higher. If you send bits across a line fast enough you're grtting into the territory of RF electronics, with wrong connector or conductor geometry you will get echos on the line and all kind of signal loss. A good digital protocol should keep this at bay with error…

I just need to make a cable with better eye diagrams so I can market it to AV enthusiasts with "golden eyes"!

Re: A nearly perfect USB cable tester

#26

Post by TeMPOraL »

graemep wrote: post #13
Gigachad wrote: 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…

I suspect most users do not even realise things are slow.

Oh, they very much do. But like with everything in technology, they can do fuck all about it, so they resign and maybe complain to you occasionally if you're the designated (in)voluntary tech support person for your family and friends.

Regular people hate technology, both for how magical and how badly broken it is, but they've long learned they're powerless to change it - nobody listens to their complaints, and the whole market is supply-driven, i.e. you get to choose from what vendors graciously put on the market, not from what the space of possible devices.

Re: A nearly perfect USB cable tester

#27

Post by QuantumNomad_ »

Gigachad wrote: 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…

On iPhone, when connecting an external MIDI device via USB, the phone told me that the device was drawing too much power and would be disabled.

I don’t know if they check that via USB protocol, or if they are measuring the actual power draw on the USB port.

In order to use the device, I had to connect it via an externally powered USB hub.

Re: A nearly perfect USB cable tester

#28

Post by TeMPOraL »

jmalicki wrote: post #25
atoav wrote: post #19

Earlier quoted context omitted.

No. What I am saying is that it is hard to test the quality of a 8K 240Hz 4444 video cable without having a device that can send and receive this or even higher. If you send bits across a line fast enough you're grtting into the territory of RF electronics, with wrong connector or conductor geometry you will get echos on the line and all kind of signal loss. A good digital protocol should keep this at bay with error…

I just need to make a cable with better eye diagrams so I can market it to AV enthusiasts with "golden eyes"!

Our cables are so good that their eye diagrams look like a photograph of a cross-section a gold analog AV connector. That is not a coincidence!

Re: A nearly perfect USB cable tester

#29

Post by ChrisMarshallNY »

This isn't a Beagle. When I first read the headline, I was hoping that it would be more than a smart continuity tester.

It seems to be a more comprehensive "Make sure the lines go where they are supposed to" tester. Looks pretty good.

But the devices that test things like transmission speed, are a lot more expensive.

I think that many of the issues that this device tests, can be mitigated by simply buying cables from reputable sources.

Re: A nearly perfect USB cable tester

#30

Post by atoav »

jmalicki wrote: post #25
atoav wrote: post #19

Earlier quoted context omitted.

No. What I am saying is that it is hard to test the quality of a 8K 240Hz 4444 video cable without having a device that can send and receive this or even higher. If you send bits across a line fast enough you're grtting into the territory of RF electronics, with wrong connector or conductor geometry you will get echos on the line and all kind of signal loss. A good digital protocol should keep this at bay with error…

I just need to make a cable with better eye diagrams so I can market it to AV enthusiasts with "golden eyes"!

Well the thing is better doesn't mean better quality here. Better means you can use a longer cable or abuse the cable for longer till it dies.

This is a big part of what makes any pro gear expensive: reliability. If you just connect your home hifi to your speakers in an acoustically untreated space, you could also just use a bunch of steel wire coathangers and get an indistinguishable result. Even a el-cheapo store brand music shop cable will do the trick for years if you don't habitually change your setup four times a week (most people don't).

But if you need reliability and predictability in a studio or live context giving a damn about cable quality is mandatory since a broken cable in the wrong place can ruin your day and reputation. But it is an absolute myth that they will affect the sound in any meaningful way.

Exeption: guitar cables. The capacitance of guitar cables can shift the resonance frequency of the pickup up or down leading to audibly different results. But that id no magic either, you could just take a low capacitance cable and add in arbitrary capacitor for 10 cents as needed.

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