I had a fairly inexpensive setup for iTunes (mostly 'mastered for iTunes' AACs but a fair number of ALACs as well)
mac mini 2011 > FiiO E17 > Qinpu A6000 MKII > 2.1 Polk Audio setup (RTiA1 plus Polk Audio Subwoofer)
I replaced the 24/96 FiiO with this 24/192 PHA-2 and it made a huge difference.
The system was already pretty awesome, but now it's just fantastic, especially for a relatively inexpensive and low footprint system.
I love the limited time I have I can turn the Qinpu up to halfway and just ride it out without any distortion other than rattling the wood frames in my windows.
Also using some early 1960's WE 396A's in there, they are smooth tubes :)