pipelineaudio wrote on Fri, 08 September 2006 17:29 |
Sahib I think the question is, IF there are going to be errors. Lets say the cd player plays back at 1X speed in realtime, with a very short buffer. In this cae could there be less errors between transports? I'm just trying to determine if there is ANY possible mechanism of difference to the output audio between a 20 dollar transport and a 6000 dollar transport, if they are feeding the same DAC |
pipelineaudio wrote on Sat, 09 September 2006 01:46 |
shouldnt they just buffer largely anyway so like on a cd holding computer programs, it could be surely played with NO errors? Or is that wishful thinking |
mdemeyer wrote on Tue, 12 September 2006 05:48 |
The original post didn't say (clearly, at least to me) if he was talking about difference in CD playback when the transport was driving a DAC directly or some kind of PC setup. If the former, the DAC clock is being picked up from the S/PDIF (or AES/EBU) signal and, depending on the implementation, the signal from the transport can impact the sound not because it has bad data, but because of jitter in the recovered clock. This is a well known and measurable item. Want to clarify the question? |
mdemeyer wrote on Mon, 11 September 2006 23:48 |
The original post didn't say (clearly, at least to me) if he was talking about difference in CD playback when the transport was driving a DAC directly or some kind of PC setup. If the former, the DAC clock is being picked up from the S/PDIF (or AES/EBU) signal and, depending on the implementation, the signal from the transport can impact the sound not because it has bad data, but because of jitter in the recovered clock. This is a well known and measurable item. Want to clarify the question? |
Sin x/x wrote on Tue, 12 September 2006 12:26 |
The quality of digital audio depends only on the quality of the converters. If you hear sound difference between cd-transports, there's a design fault in the dac. |
Jon Hodgson wrote on Tue, 12 September 2006 07:49 | ||
Dan has a good paper on jitter and phase locked loops on his website. |
Jon Hodgson wrote on Tue, 12 September 2006 07:49 |
A perfect transport would have zero jitter on the output. A perfect PLL would have 100% jitter rejection, a perfect PLL is not easy, which is why Lavry products have CrystalLock. If you can hear a difference due to jitter on the output of the transport, then they are BOTH imperfect. |
Jon Hodgson wrote on Tue, 12 September 2006 07:49 |
And that is only covering the subject of jitter, if the transport is inferior enough that it has more read errors, and/or the interpolation method is inferior, then you might also hear a sound difference.... though to be honest I suspect it's a fairly moot point, even cheap mechanisms can usually manage 100% data recovery once combined with the extra level of redundancy which is used on a data CD, which indicates that their read errors are kept under control. |
Sin x/x wrote on Tue, 12 September 2006 18:40 | ||||
I can't find the paper on jitter and phase locked loops on Mr.Lavry's website. |
Quote: | ||
No, only the pll's in the converter needs to be good enough. Then all jitter is rejected. |
Quote: | ||
If the read errors are within a certain range, or don't exceed a certain range, then all errors are corrected. |
Ronny wrote on Tue, 12 September 2006 20:52 |
Yes, but is any converter actually totally 100% jitter free? Ala what we old timers used to call the holy DAC. Jitter immunized maybe, jitter free, I'm not so sure. If it's not audible but still measurable, that doesn't make it a 100% elimination of all jitter. For all practical audio purposes the reduction of jitter well below audible should be sufficient, should it not? |
Jon Hodgson wrote on Tue, 12 September 2006 13:13 | ||||||||||
Look on the support page, "White Papers"->"On Jitter"
And how does that contradict what I just said? For you to hear a difference caused by jitter requires that there be jitter in the first place, AND that your converter does not reject it completely. |