Bits are bits? Why a USB cable might matter

Joey_V

Apparently when your computer sends data to another storage device or unit, there is a check sum at the receiving unit and if a data set is bad then the transmission is retried.

Hence a bad usb cable only causes delay of transfer of data or bits.

In audio, the signal is tried once. So in theory a corrupted audio data set will not be corrected. Hence a good usb cable is needed.

https://www.edn.com/design/consumer/4376143/Fundamentals-of-USB-Audio

machone

Joey_V wrote: »

Apparently when your computer sends data to another storage device or unit, there is a check sum at the receiving unit and if a data set is bad then the transmission is retried.

Hence a bad usb cable only causes delay of transfer of data or bits.

In audio, the signal is tried once. So in theory a corrupted audio data set will not be corrected. Hence a good usb cable is needed.

https://www.edn.com/design/consumer/4376143/Fundamentals-of-USB-Audio

And clean power helps to prevent these packet errors.

GospelTruth

Interesting article and informative which spurred me to do a little extra research.

In looking at the different transfer mechanisms, you would think that any device supporting USB music playback would not use bulk transfer. It would make sense then why a good USB cable would be needed if you weren't validating the data using checksums and resending data.

I wanted to see if I could find out about my OPPO UDP-203 and see what transfer methods it's USB input used/supported. In looking at the OPPO UDP-203 manual, it states specifically:

This unit supports “USB Mass Storage Class Bulk-Only Transport” devices only. Most USB
thumbs drives, portable hard disk drives and card readers conform to this device class. Other
USB devices such as MP3 players, digital cameras, and mobile phones may not be
compatible.

So this device only supports Bulk Transfer. That leads me to conclude that it is somehow storing the data in memory and buffering to make sure bit for bit transfer is complete. This is not the mechanism you would think would be used for music playback such as Isochronous (transfers are used to transfer data in real-time between host and device).

So while I see that a USB cable might matter in some instances like Isochronous, it doesn't appear so in this case with the OPPO. It would be interesting to see what devices support USB and for what transfer mechanisms. That might lead someone to determine if buying a higher end USB cable is worth it or not.

rpf65

If everything in the chain mattered, one would have to assume the lowly USB cable would matter.

I personally feel that there was a noticeable difference when I went to a higher quality HDMI cable, and that is a purely digital transfer, a lot more than USB, but still digital. I don’t know why, could simply be better termination, or any number of simple things, but there was an improvement.

I think the same would apply to a USB cable.

It seems the laws of diminishing returns returns happened rather quickly when testing HDMI cables. I would assume that since USB is utilized for substantially less data transfer than HDMI, that diminishing returns would be noticed more quickly.

With that said, if I were to purchase a USB cable, I would be much more comfortable spending the extra money on a substantially more expensive USB cable from a quality manufacturer than the “it’s just as good, besides it’s only ones and zeros being sent so it doesn’t matter” manufacturer.

pitdogg2

The biggest thing in USB cables recently is putting the power wire in its own jacket outside of the data cable. Personally I think that was a step in the right direction to knock down the noise that historically was the biggest complaint with USB cables.
IMHO

mhardy6647

... even though the power line in USB is DC?

gudnoyez

This Wireworld Starlight 7 made a difference for me.