In Reply to: Other than jitter and bitperfect? posted by Gevo on November 30, 2009 at 09:01:06:
The USB receiver still works the same way to sync up to the USB datastream, and still has its own fixed and PLL derived clocks running in the DAC, so still most likely propagates the same jitter signature as with a normal adapative isochronous connection. It's just that with the asynch iso mode you can use a local (high quality) clock for control of the USB receiver codec outputs to the DAC chip (clock, data and enable). Jitter will still be on the signals, but can be much reduced with good layout and isolation techniques. In a perfect setup, the cable shouldn't matter, but hard to achieve that in the real world with all of the many clocks and data processing in a USB receiver, along with noisy power lines from the computer, and the resulting jitter noise added to all of the signals. It takes more than a clock to convert digital data to analog, so timing irregularities on any of the signals will be translated to jitter on the clock since they all share the same current return, and there will always be a voltage-inducing impedance in that return.
So the effects of the cable are the same, but there is the opportunity to reduce how much gets to the analog output with async iso mode.
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- Cable effects same regardless of USB mode - Slider 09:48:40 11/30/09 (20)
- RE: Cable effects same regardless of USB mode - fmak 23:33:07 11/30/09 (0)
- RE: Cable effects same regardless of USB mode - John Swenson 13:18:47 11/30/09 (18)
- RE: Cable effects same regardless of USB mode - Roseval 03:50:17 12/02/09 (5)
- RE: Cable effects same regardless of USB mode - John Swenson 12:11:57 12/02/09 (4)
- RE: Cable effects same regardless of USB mode - Roseval 13:33:52 12/02/09 (0)
- RE: Cable effects same regardless of USB mode - idiot_savant 13:32:06 12/02/09 (2)
- RE: Cable effects same regardless of USB mode - John Swenson 14:53:01 12/02/09 (1)
- RE: Cable effects same regardless of USB mode - idiot_savant 15:52:12 12/02/09 (0)
- Nicely said John(NT) - audioengr 18:47:57 11/30/09 (0)
- RE: Cable effects same regardless of USB mode - Tony Lauck 13:33:30 11/30/09 (10)
- RE: Cable effects same regardless of USB mode - John Swenson 15:47:48 11/30/09 (9)
- What length usb sounds best, in your experience?nt - JB 07:32:48 12/02/09 (2)
- RE: What length usb sounds best, in your experience?nt - John Swenson 12:01:00 12/02/09 (0)
- RE: What length usb sounds best, in your experience?nt - jkeny 09:59:35 12/02/09 (0)
- RE: Cable effects same regardless of USB mode - audioengr 18:52:39 11/30/09 (4)
- RE: Cable effects same regardless of USB mode - drrd 04:08:00 12/01/09 (2)
- RE: Cable effects same regardless of USB mode - fmak 05:36:46 12/01/09 (1)
- RE: Cable effects same regardless of USB mode - drrd 06:48:36 12/01/09 (0)
- RE: Cable effects same regardless of USB mode - deskducker 19:34:44 11/30/09 (0)
- RE: Cable effects same regardless of USB mode - Thomas James 17:45:21 11/30/09 (0)