downloading music versus cd `s quality


Greetings
I have been reading a lot about quality of digital music, and the question is: can I transfer all my cd~ to my Mac, then upgrade the sound quality on the Mac , via a software program, or do I need to start from scratch and download music that is already in HD?
also, can someone explain the difference between regular cd and 24 Bit/192kHz ? What is the best way to get digital quality music, in other words? Much obliged.
I am a digital neophyte!
rockanroller

Showing 2 responses by rockanroller

So, after reading all those answers a few times, here are two questions:
one: audio software:does anyone recommends any audio software upgrade such as Amarra or any other, which would lead to the fact that can you really upsample, or is it a misnomer, and the only form of HD digital audio are only select companies?
two: budget DAC ! is the difference in price of DAC`s really indicative of quality, or can you get something good for about $ 700, made for computer versus cd players ?
three: connect: is it better to use HDMI, or digital coaxial?
Whoaah! thank you for the lessons.