does it logical to invest on expensive transport?

Yes, absolutely a really good trasnport will improve performance. Absolutely no question about it. Anybody who says that it won't hasn't ever heard a good transport vs. a average one.

Are hi-res digital files better than the CD? No, at best, they are the same as the CD from which they were/are copied.

Can a server based source compare to direct from CD? Yes, with a good DAC.

Should you buy a really good transport? Depends on what you see for your future. Server based systems are very convenient and done right with a very good DAC can be truly great.

Teajay makes a good point, if you have a large collection of CDs that you prize and have no plans to download, a high quality transport is mandatory for optimal redbook performance. It`s amazing just how good redbook can sound in a well thought out system, old fashioned? but still excellent sound without question.

the ps audio perfect wave transport retails for $3000 and should be considered. it plays hi rez and is versatile as to its digital outputs. listen first before buying.

i have been told that there are number available for sale used on audiogon.

Mrtennis, I have to bust your chops on that statement (good heartedly of course):

"i have been told that there are number available for sale used on audiogon."

what are you too lazy to actually read the listings on Agon and must rely on word-of-mouth as to what is listed for sale? After all, you are/were on the site when you posted.

Cheers though to you ;-)

Yes, a good transport will make a considerable difference. $15K!!! Where were you when I was actively selling audio and was being told that $ 2000 for an amp was way too high. Seriously, $15K is more than I would spend, I have never spent a third that much for any component and I have some very good equipment.