Like many here I spent many hours of frustration trying to decide how to set up a hi-rez digital source. I had free access to a loaner Ayre QB-9 and was determined to hear it at it's full potential.
Here is the short story.
Had my very capable 30 yr old nephew/IT/network admin/computer professional build a laptop to the specs I found at genesisloudspeakers.com/support/newsletters.He made a few changes of his own to lessen expense and time as this was experimental. Used a newer PC running windows 7 with I5 pentium processor, 6GB Ram, 750GB HD that I bought on closeout at Office Depot.
Used my I phone for the remote, ran Foobar2000 and connected it with Audioquest Coffee USB.
My system: B&W 802D, Krell KCT Preamp, Cello Duet 350, Reality speaker cables, Esoteric Strings RCA from QB-9 to Krell.
Al audio files are FLAC files from my CD stock and some 24/96 albums and various downloads.
The results are jaw dropping. Some of the flac files from redbook CD's are very hard to distinguish from 24/96 files.
The sound with the KCT lacks almost nothing, Resolute but just diffuse enough to not sound digital, no hard leading edge and all Krell base.
Tried it with the AYRE K5xe-MP preamp and it was not as good as the KCT in my system. But tried both preamps in an all Ayre system with Vandersteen 3A and the Ayre preamp was better.
The Laptop works flawlessly, it is hard wired to my network, as we shut the wireless down as part of the modifications. Using the I-phone remote app is so cool and the change from song or album is instantaneous with absolutely silent operation.
Am now trying to decide on looking at higher priced dacs or stopping at the QB-9.
Hope this helps, I spent 8 months finding this info and deciding on this course of action.