"tutorial" on computer music servers

As Steve Nugent mentioned the 2009 MacMini would be a great start. His website has a lot of information on how to easily configure one for very good sound. I went this route with an Audiophilleo USB converter and my existing DAC. if you want to use iTunes as the interface Audirvana is a good music playback software choice. If you want to bypass iTunes I recommend Jriver. You could probably do all of this for under $1000.

http://www.linkwitzlab.com/dCS_Guide_to_Computer_Audio(2).pdf

Check out Bryston BDP-1 or BDP-2. It's basically a transport for digital music.

Just connect external USB Drive with your music to the Bryston. Since music is loaded into memory before play, quality of USB cable will not effect sound quality. Then connect the Bryston to your DAC.

There are many options where you can install an internal drive, control with iPad/iPhone ...

It's pricey so you pay for convenience/plug and play. Google reviews for more info.

I also recommend DLNA but requires some computer knowledge.

I second the Bryston. No comparison with the puter based systems, PC or Mac. It takes everything out of the equation (computer programing USB, upgrading the mini power supply, deciding on which $600 softwear package, driver & compatability issues,cant switch between redbook & hires problems...) except the MUSIC.

I am surprised at your comments on redbook CDs. I have CDs produced in the 80's, and except for a very few exceptions, I can get almost all my 400+s cds still today. I also have a vinyl collection of mostly 70's rock and have duplicated most of it in CD. There are a few rare albums like Marty Balin's Bodacious DF which is difficult to find in CD (although its available for big bucks). Spend some time on Amazon. You'll be amazed at what is still available on CD. The record companies have discovered many of the older stuff is still in demand and are releasing remastered versions (Boz Scaggs 1st album is an example).

You can also check on the SHM type Japanese pressings where the Japanese record companies are resurrecting late 60's and early 70's rock. Groups like Emmerson Lake and Palmer, King Crimson, Savoy Brown, Brian Auger, etc are available in special pressings.

I second Knghifi re the Bryston products. I went to the Bryston BDA/BDP combo from a PS Audio PWT and I am not looking back. Ripped standard redbook CDs have never sounded better, and I am hearing things on ripped CD I have never heard before. I use dBpoweramp to do the ripping to .flac files. dBpoweramp also allows you to process older recordings with a digital equalizer and volume normalizer to improve those thin, old 60's recordings. I rip those to 24 bit with a bit of EQ and they sound amazing.