however way you cut it, the cd format (red book) is limited to 16 bit/44khz resolution. that is the physical limit of the software. that little shiney disc can only hold that info.
in general, there are 2 ways to "enhance" or alter the amount of "resolution" that actually comes out of the analog output of your cdp or dac.
first, processes can be imbedded into the 16/44 signal that can be interpreted by the appropriate filter/dac to "noise-shape" or "enhance" the sound; the best known of these is HDCD. another would be Dolby Pro-Logic. these methods don't add data but give the dac clues to "shape" or "adjust" the sound. they don't ADD resolution.
the second, and currently popular method, is over-sampling and up-sampling. these methods take the 16/44 data and either add bits to the 16 bit word (commonly to 18, 20, or 24) or add more samples in between the 44khz samples (usually, but not always in multiples of 44khz; 88khz, 96khz, 172khz, 192khz, or even 768khz). these methods are attempting to reduce the negative effects of the 20.5 khz digital filter on red book, reduce noise, or add "ease" or "presence" to the sound. none of these methods ADD resolution. they may make the sound more listenable or enjoyable. and therefore "better".
i have dramatically oversimplified my explaination but the fact is that no format can create information not on the original software. they can only manipulate data and change the perception of how it feels or sounds.
so all cd players and dacs input the same resolution, manipulate the data to some degree and output an analog signal. i have seen very little corelation between the ultimate sampling rate of their chosen manipulation scheme and performance so far (but many disagree with me).
there are certainly differences between resolution of various cdps, transports and dacs. but these differences have to do with the quality and execution of the designs, and not creating "new" resolution from 16/44 software.
