I haven't a clue but there is some interesting reading.
"Gang,
Look there are 2 cables inside a USB cable. There is the DATA differential pair that must be designed for traffic up to at least 12Mhz and the POWER cable which is VBUS 5V's and Ground.
I have like tons of cables now and some do sound different. But remember it will be device dependent.
All of the PCM27xx devices require VBUS to determine the computer is there. This means there is current running from the computer to the USB Device via the POWER side of the cable.
Other devices like the TAS1020 look for signal on the DATA portion of the cable only. Therefore the VBUS is not used and only the Ground connection on the POWER side is used.
On the DATA side termination on the Device side or endpoint will have an effect on transmissions. I usually get the 5M cables put them on a couple of computers with my USB analyzer on the DAC side and check for errors.
It's not suggested to use a 5M with streaming audio. These cables were meant for low speed devices. 2M and under for audio will make all the difference in the world.
With the POWER side being used it can bleed noise from the computer into the dac.
It would be nice if you could switch the VBUS signal on the computer side from VBUS to Ground if your device doesn't use it.
Anyways another thing about the POWER side of the cable is that noise from the computer can end up on the device. The cable should do all it can to make sure that doesn't happen.
It's best like all aspects of this hobby to try this stuff before you buy it.
Remember using these expensive cables on a hard drive is worthless they are in Block mode not Streaming and will not be effected by the use of costly cables.
Thanks
Gordon
J. Gordon Rankin"
"audioengr
Facilitator
Posts: 1953
Gallery
Systems
Re: All USB ports are not the same
« Reply #8 on: 6 Dec 2008, 07:10 PM »
Quote
Quote from: drubin on 6 Dec 2008, 06:56 AM
Quote from: audioengr on 6 Dec 2008, 04:14 AM
There are some really good USB cables out there now, including the Axis and the Polestar and the Poiema from Ridge Street Audio.
Thinking ahead to my forthcoming Offramp Turbo3, will the quality of the USB cable make a big difference? Currently, I have the Mac Mini in the audio rack so I can use a 1M Ridge Street USB cable. But I'm kind of intrigued about the long cable you include with the Offramp as it presents some interesting options for rearranging my system.
Yes, the USB cable will make a difference. If you want to stay at 5m, then the Polestar is what I would recommend. If you want to have the very best and keep it short, 1-2m, then the Ridge Street or Axis. I can get any of these for you and ship it with the Off-Ramp 3. Same price for the cables.
Steve N."
Lots of talk about Synergistics Research
http://www.synergisticresearch.com/tesla-series/tesla-series-digital-cables/tricon-usb/
Good luck with it.
"Gang,
Look there are 2 cables inside a USB cable. There is the DATA differential pair that must be designed for traffic up to at least 12Mhz and the POWER cable which is VBUS 5V's and Ground.
I have like tons of cables now and some do sound different. But remember it will be device dependent.
All of the PCM27xx devices require VBUS to determine the computer is there. This means there is current running from the computer to the USB Device via the POWER side of the cable.
Other devices like the TAS1020 look for signal on the DATA portion of the cable only. Therefore the VBUS is not used and only the Ground connection on the POWER side is used.
On the DATA side termination on the Device side or endpoint will have an effect on transmissions. I usually get the 5M cables put them on a couple of computers with my USB analyzer on the DAC side and check for errors.
It's not suggested to use a 5M with streaming audio. These cables were meant for low speed devices. 2M and under for audio will make all the difference in the world.
With the POWER side being used it can bleed noise from the computer into the dac.
It would be nice if you could switch the VBUS signal on the computer side from VBUS to Ground if your device doesn't use it.
Anyways another thing about the POWER side of the cable is that noise from the computer can end up on the device. The cable should do all it can to make sure that doesn't happen.
It's best like all aspects of this hobby to try this stuff before you buy it.
Remember using these expensive cables on a hard drive is worthless they are in Block mode not Streaming and will not be effected by the use of costly cables.
Thanks
Gordon
J. Gordon Rankin"
"audioengr
Facilitator
Posts: 1953
Gallery
Systems
Re: All USB ports are not the same
« Reply #8 on: 6 Dec 2008, 07:10 PM »
Quote
Quote from: drubin on 6 Dec 2008, 06:56 AM
Quote from: audioengr on 6 Dec 2008, 04:14 AM
There are some really good USB cables out there now, including the Axis and the Polestar and the Poiema from Ridge Street Audio.
Thinking ahead to my forthcoming Offramp Turbo3, will the quality of the USB cable make a big difference? Currently, I have the Mac Mini in the audio rack so I can use a 1M Ridge Street USB cable. But I'm kind of intrigued about the long cable you include with the Offramp as it presents some interesting options for rearranging my system.
Yes, the USB cable will make a difference. If you want to stay at 5m, then the Polestar is what I would recommend. If you want to have the very best and keep it short, 1-2m, then the Ridge Street or Axis. I can get any of these for you and ship it with the Off-Ramp 3. Same price for the cables.
Steve N."
Lots of talk about Synergistics Research
http://www.synergisticresearch.com/tesla-series/tesla-series-digital-cables/tricon-usb/
Good luck with it.