Using the internal sound card with good optical A/D converters?

Question

Dear Logic users, I have two questions:
1) I was wondering if the internal sound card of my MacBook is of such quality that I can achieve good results if I bought a good A/D converter with a digital output to plug directly into the optical line in of the MacBook? E.g. the Samson C-valve http://www.samsontech.com/products/productpage.cfm?prodID=1651&brandID=2 along with the M-Audio Co2 http://www.m-audio.com/products/en_us/CO2-main.html to convert the coaxial S/PDIF to optical? (Same procedure for the line out signal, with a D/A converter of course.) Or is the internal sound card of such inferior quality that I should stick with my current MBox 2 Pro? My initial thought was that if the signal is kept within the digital realm, it is really the A/D converters that determine the sound quality, and that the internal sound card of my MacBook does little less than calculate the digital signal. Maybe someone with a more intimate knowledge of how the internal sound card works with digital I/O could chime in?
2) If the above mentioned approach would be feasible, suggestions of other A/D and D/A converters would be most welcome.
The reason for this is to be free from the driver issues that sometimes occur with external hardware, especially with software/OS upgrades.

Answer 1

If you are recording Midi using loops and all it wont make a difference in having a AD/ converter. as everything you are doing is in the box.
However if you want to get a Analogue signal into the computer then its a different case, and I'm not talking about using Optical from a keyboard, and even if i was you would need to have a converter anyway,
even though i am talking about Recording Vocals or Live instrument!
This is where the Converters come into play, be aware Converter and sound-cards are two different source of hardware,
anyway Back to Converters on live vocals this is where the AD comes into play,
transferring Analogue Signal into Digital,
and also getting used to the sound of the converts, or even liking the the sound of the converters/soundcard which is always going to be subjective and which also shares a relation with Near-field monitors,
you change your monitors and it seems as if your sound changes that is how tight the relation is between the two.
Fr.BlayZay.