FireStone Audio BlackKey USB Digital Audio Converter

For the price it sells for right now... pretty hard to beat.. i have this hooked up to my computer and then to a early 90s Pioneer VSX-D1S (monster class 135WPC (real watts not today's ht receiver watts)) receiver with a pair of vintage DCM Timeframe TF250 speakers. The sound quality is excellent...kewl little device you might want to order a usb extension cable as this thing is pretty big and may not fit usb ports on motherboard or will certainly block adjacent ports.I'm well pleased with this item... if you can get it for the low price ($30 when i bought it) it is a great deal.

Macbook Pro 15" / Mavericks / BitPerfect - this little beauty gives me 24/96 over USB. Sounds light, airy, and clean. No noticeable freq bumps, PRaT is quick as well, amp can drive my Senn 598's to a reasonable level.Don't usually leave reviews on Amazon, but had to offset the one star rating for this since there is nothing wrong with my unit..Update 1/8/2014 - works on an iPhone 5s/iOS7 via a small, cheap unpowered USB hub and the Apple lightning->USB adapter. Won't work w/o the hub, however.

Sounds pretty good, probably won't do better at around 30 bucks. Plug n play with windows 7 but had to restart once, sounded like latency problem but restart and replug and worked fine. very good bass, forward mids, good tone, treble was sort of rolled off compared to my idecco. only listened with a pair of the 8020 earbuds which were an internet sensation a while back. now i want a desktop headamp since theres only so much a usb powered amp can do. Pretty good sound to me, and im picky about audio. Enjoying tunes at work off youtube, probably do better with better quality files and/ or setup other than plug n play. Recommended highly.