A DAC that doesn't separate itself from the player with its own clocking must rely upon a very expensive player and a very expensive digital cable for the timing and delivery of the bits. That is, for the feeding of the bits to the digital converter chip.
Some modern DACs, in different ways--some more successful than others, have overcome this problem by reclocking the data making it possible to use a wide variety of relatively inexpensive players, including those that play SACDs and DVDs as well as CDs. They can do this with no sacrifice of audio quality on that account.
Of course how they handle the analog signal delivered from the converter chip will always have an effect on the sound.
Some modern DACs, in different ways--some more successful than others, have overcome this problem by reclocking the data making it possible to use a wide variety of relatively inexpensive players, including those that play SACDs and DVDs as well as CDs. They can do this with no sacrifice of audio quality on that account.
Of course how they handle the analog signal delivered from the converter chip will always have an effect on the sound.