Hi-end sound from iTunes running on MacPro

I believe it's still a volatile marketplace. The good thing is that the DACs for file servers are not that expensive. The one to watch at the moment appears to be the Mytek at $1500. Connect to your MacPro using FireWire. You can use the balanced outputs to your preamp.

I own the Metric Halo LIO-8 which has a more complex set of features, was twice the price, and has very good sound. But if I were buying today, I'd try the Mytek.

Regards,

First, upgrade your iTunes playback performance by purchasing Pure Music. This runs in conjunction with iTunes and makes it sound better.

Then, make sure you rip with the best software, not itunes. Rip using free XLD:

http://tmkk.pv.land.to/xld/index_e.html

Ripping to AIFF or ALAC format is not as good a .wav, but retains all of the tags.

Then select the best USB interface so that jitter is minimized. This is actually more important than the DAC. Most DACs have poor built-in async or adaptive USB interfaces.

USB converter options that do not dissappoint are: Empirical Audio Off-Ramp 5, Synergistic Research, Diverter HR and if you are on a budget, Audiophilleo.

Then, get a decent DAC like Wired 4 Sound DAC2 or Metrum Octave. Some like the Rega. The W4S DAC2 when driven from I2S cable is world-class. Sound like you have never heard before.

Steve N.
Empirical Audio

Silly question but..... what can be done with my current library of iTunes music? and... is there a similar music database like iTunes store where I can find an extensive library of WAV or FLAC?

I recommend Audirvana Plus instead of Pure Music. It's heck of a lot cheaper and sounds IMHO very good, better than 1.86 of Pure Music. IMHO Audirvana v11 beta that I am using with Direct and Integer mode in Mountain Lion is superior to the other music apps I have tried (including Amarra 2.4.5)

I'm still waiting for a proper fix from Pure Music for iTunes11/Mountain Lion before I try it on my Macs.

Another option if you don't need DSD playback, is to get BitPerfect. Cheapest of the lot and sounds very close to Audirvana.

If you already use a Mac, I recommend continuing the use of iTunes. iTunes supports WAV as well, though I find AIFF sounds just as good as WAV while still supporting meta data (album art/artist/track/album details).

I think if you want "high end" sound from the Mac, you will need to put in some work. I downloaded a free copy of an OS X optimization guide from UltraFi a while back and it's now for sale on iBooks. That can help you shut down the extraneous system processes in OS X that aren't needed for music playback. Obviously, this means you shouldn't really use the Mac for anything but music playback. Audirvana Plus has a System Optimizer which is a very easy to use method of disabling some of the background processes but not as comprehensive as the UltraFi guide.

You can also try switching the HDD to SSD and upgrading the RAM to the largest supported. 4GB should be good enough for CD quality, but if you are planning on getting stuff from HD Tracks, I think 8GB should be the minimum.

I have tried many players on the Mac and Pure Music is good but the best I find is actually one of the cheapest - BitPerfect:
https://itunes.apple.com/au/app/bitperfect/id455545700?mt=12

As to the DAC Steve's suggestion of a WFS is true - fed with I2S it is indeed very good and world class but for my taste slightly analytical - but this is a personal preference thing. As to what to feed it, Steve cant mention this because he is the maker, but his Off-Ramp is the best.

The Metrum and NAD M51 are also very good and both benefit from Steve's Off-Ramp - especially the Metrum.

Another excellent option is Steve's Overdrive DAC:
http://www.empiricalaudio.com/products/

Still another option is the PDX which is my favorite USB DAC:
http://www.lenehanaudio.com.au/index.php/products/pdx-usb-dac.html

Disclosure:
I live close to the maker of the PDX and go down there all the time to check out their stuff as well as owning a lot of their gear which probably makes me biased.

Thanks
Bill