This is a technical question that came up over on the Steve Hoffman Music Forums (SHMF). I hope that Ted Smith and some of the other technical gurus at PS Audio can help clarify this. In a thread the statement was made that the sound of a well designed DAC will not depend on quality of the transport or the cable connecting the two together. The reasoning behind this is that a well designed DAC well take the digital data that is sent to it and re-clock it and do all of the things needed ( such as noise shaping, dithering, etc. ) to get the best analog signal out of the digital data. Seems reasonable.
For the last four or so years I have used a PS Audio DMP and DS DAC ( which now runs Windom firmware ). I was told from day one of my purchase to use the HDMI I2S connection between the two to get the lowest jitter performance from the combination of the two. That seems to say that the best quality sound from the DAC depends on the connection between it and the transport.
Recently I traded-in my DMP for a PS Audio PST. And, to my pleasant surprise, I hear even better sound quality from the combination of the PST and my same DS DAC. I am still using the same I2S HDMI connection and the only change has been the PST for the DMP. The music sounds noticeably clearer with the PST and other PST users have said the same thing. This has been attributed to the galvanic isolation used in the PST, but again this seems to say that the sound of the DAC depends on the transport.
Now I believe that even though the PST does not say so in its name it is also a memory player just like the DMP. It takes the data from the disc and buffers it and re-clocks it before sending via the I2S HDMI interface to the DAC. Does the DS DAC then re-clock the data again when it gets to it. So what I am asking is can someone explain to me in high level technical terms who does what to the data in the PST / DS DAC combination?