I have the Airmotiv 5's and currently have them connected directly to my computer using a $3 3.5mm to RCA adapter. I'm looking at either the Emotiva XDA-2 DAC or possibly the UMC-200 7.1 prepro so I can also use it as an HDMI+Audio switcher for several computers I have in my computer room. Emotiva has a couple more DACs/Processors coming down the pike that will probably have both analog and digital inputs, namely the Stealth DC-1 and Executive Pre-1. These two will be half-rack, 2U boxes instead of a full-rack box.
I'm getting absolutely NO background hum/noise on the Airmotiv 5's using the built-in Realtek ALC-889 chipset with an analog connection.
I'd consider the Emotiva XDA-2 because there are very few, if any, DACs in the $400 range that use the C-Media 6631 USB chipset that can stream 24/192 via USB. The only real negative is the lack of analog input on the XDA-2 for tape decks, turntables, etc.
HD-DVD = 94
Blu-Ray = 120 ( 24 Warner red2blu )