usb cables?

[sandyk]

1 hour ago, PeterSt said:

As long as these aspects are not understood, all USB cables will sound the same.

 

If no bit errors, they will all sound the same, at least to Mansr

7 minutes ago, One and a half said:

The best way to improve USB is not to use it.

 

Unfortunately, some are forced to use it if they want DSD.

[sandyk]

22 minutes ago, GUTB said:

I need a good 15-20 feet of USB cable to run across my listening room from my audio PC to the DAC. I have Supra cable which does this and it works fine,

I.M.E.  Any USB cable >3M long used without Regeneration will reduce SQ to some degree , in part due to RF/EMI issues, and in some  cases the connected USB device will not function correctly, or perhaps even be identified due to excessive voltage drop with the incoming +5V rail.  This is governed by the size of the conductors stipulated in the USB standards with many cables using thinner conductors than permitted.

 

(The 2.0 specification limits the length of a cable between USB 2.0 devices (Full Speed or Hi-Speed) to 5 meters (or about 16 feet and 5 inches).

[sandyk]

7 hours ago, mansr said:

The USB 2.0 standard does not specify wire gauge for any of the conductors.

 

 I have seen specifications for the 2 almost universally used wire gauges. Many USB cables use the thinner gauge, and you can often tell simply by looking at the thickness of the cable.

[sandyk]

6 hours ago, manisandher said:

Something is causing the sound to change, without changing any bits.

 Hi Mani

You will never get the " all  USB certified cables sound the same" brigade to accept this, let alone co-operate in such an endeavour.

Even if you get confirmation by way of DBTs they will find some way to dispute the results.

 Regards

Alex

[sandyk]

6 minutes ago, mansr said:

I looked up the requirements in the actual spec before replying.

 I don't give a rat's rear end what you did.

As I said, I have seen 2 different wire gauges quoted that are almost universally used, perhaps for wire gauge suitability and availability, and commercial reasons.

[sandyk]

1 hour ago, mansr said:

Why is it called an "attack" when people with real knowledge on the topic share some of their expertise?

 

Textbook knowledge and real life practice are very different things in this particular area.

 I don't doubt that there are numerous forum members with capability of demonstrating these differences between certified USB cables of their own choosing under stri8ngent DBT conditions either.

 

[sandyk]

26 minutes ago, mansr said:

Are you implying that marce doesn't have real-life experience of electronics design?

 I am not implying that either yourself or Marce don't have real life experience of electronic design in the areas that you are employed in.

 Expertise in a particular area does not automatically translate to the same degree of expertise in other areas, as much as you would both like to believe that it does.

A good engineer in the consumer equipment area also uses actual listening, (often with a panel of listeners as Barrows can testify) as well as measurements before releasing a product for sale.

[sandyk]

1 minute ago, mansr said:

Ah, the old "audio is special" argument.

 

 Then why don't you put your money where your mouth is, and resume the series of tests with Manishander, also including in those tests a comparison of his Lush USB cable with another USB certified cable of his choosing under DBT conditions !!!

[sandyk]

2 minutes ago, mansr said:

For starters, he doesn't want to. Furthermore, I'd prefer for any future testing to take place in a less chaotic environment. Lastly, the test Mani and I did had nothing to do with cables.

 Excuses, Excuses  

[sandyk]

Just now, PeterSt said:

 

Everything sounds the same.

 

 Perhaps it does to some non audiophiles with entrenched view points who would never invest in the higher quality equipment needed, including the speakers ?

[sandyk]

4 minutes ago, mansr said:

Are you GUTB?

 

No, are you? You are perhaps even more closed minded than he is.

 

[sandyk]

6 minutes ago, PeterSt said:

Btw, nothing measurable either.

 Not even to the N.S.  team who designed the LM4562(LME49720) series of opamps where they could hear clear differences in favour of the HA ( metal can version)

[sandyk]

25 minutes ago, PeterSt said:

 

I am not familiar with particularly those, but read the datasheets of them. They can't be measured by normal means. It first needs attenuation and some more tricks and multiplication to "find out" the THD.

Still, people in here think that what we can hear, should be measurable. Well, I agree. Now the how-to.

 

 Several years ago Mark (Audioman54 IIRC) posted about this in DIY Audio. He was part of the original design team before they were made redundant.

 

https://www.diyaudio.com/forums/solid-state/132471-national-opamp-inflation.html

[sandyk]

11 minutes ago, AnotherSpin said:

 

What makes you believe your "knowledge" is real?

 

 He read it in a Textbook somewhere ?

I don't doubt that he has a great deal of knowledge, but knowledge needs to be updated regularly, and where there are NUMEROUS instances of people reporting things differently  to what is currently accepted, they should be fully investigated with an open mind, using their ears too, or better still the ears of people who report such things under correctly set up DBT conditions.

 I would be surprised if Manishander  wasn't able to demonstrate this to him with a DBT comparison of his  Lush USB cable and a USB certified cable of his own selection if they were both willing to try this.

[sandyk]

On ‎8‎/‎3‎/‎2019 at 9:36 PM, Arpiben said:

 

For sake of accuracy only:

• Low Speed USB 2.0 cables  have a max propagation delay of 18ns (USB2.0 Spec. Rev2 ch 7.1.6 p166)
• Cable Mechanical Configuration and Material Requirements are provided in chapter 6.6 (USB20 Spec.Rev2)

Are you able to provide a link to chapter 6.6 , and does it also specify the wire gauges ?

[sandyk]

33 minutes ago, kumakuma said:

 

https://www.usb.org/document-library/usb-20-specification

 

Is Google broken on your computer or perhaps your search results are being degraded by an inferior power supply... 👺

 I see that you are every bit as helpful and sarcastic as you usually are.

 

I spent quite a bit of time previously and was unable to find the exact wire specifications as previously mentioned.  USB2.0 Spec.Rev2 Ch 6.6

[sandyk]

14 minutes ago, marce said:

We are talking basic electronics and physics though here,.....

In the case of the subject of this thread, practice has shown there is far more to the subject than originally published in textbooks.

If USB didn't have any well documented problems with Audio, there would be no need for devices such as USB Regens either.

We need to be mindful here too, that such devices are also  designed by well qualified designers such as John Swenson etc

 You aren't the only member of this forum who is capable of designing high performance  multi layer PCBs either.

 

[sandyk]

33 minutes ago, marce said:

Why have a personal dig?

 

Because you keep quoting your undoubted expertise in this  area, neglecting that others such as John are also well aware of RF/EMI control issues in this area too.

 Even between highly qualified E.E.s and S/W designers it is obvious that there are many areas of disagreement.

 Only with talking to and learning from other qualified people in this area, will these niggly implementation issues with USB be fully solved, instead of being dismissed as non existent. 

 Have you ever tried talking to John OTR via PM ? You may both have a great deal to learn from each other.

[sandyk]

1 minute ago, mansr said:

That's probably because there is no exact specification, only minimum requirements.

It was suggested that the reference given covered this area

 Can you quote those minimum requirements , as I have seen huge differences in the thickness of compliant USB 2.,0 .cables, where the thinner one  died in the arse at around 4M length with a USB memory stick plugged in, and the other worked at much longer lengths with no problems at all.  I have also seen a long USB .2.0 cable that had no shielding at all.

[sandyk]

O.K.

That is one that I have previously seen. There is however another commonly used thicker wire gauge

[sandyk]

40 minutes ago, marce said:

 

Deleted

[sandyk]

14 minutes ago, marce said:

 

 

Deleted

[sandyk]

16 minutes ago, PeterSt said:

 

Frank, cables can't make a difference whatsoever. Don't you know ?

 

 In these days of tight discretionary household budgets, I doubt that you get too many customers requesting a refund after purchasing your Lush cables !

 

[sandyk]

3 minutes ago, AnotherSpin said:

 

This kind of high calibre truth is revealed to scientists only.

 

And a couple of the Scientists here actually believe it too.

[sandyk]

1 hour ago, alfe said:

 

They can make money.😜

 

 They can for Peter because his Lush cables have been very well received by many A.S. members.