JDSLabs O2+ODAC DAC & Headphone Amplifier @ techPowerUp
 

JDSLabs's O2+ODAC combination combines two designs by NwAvGuy with excellent build quality and a sturdy enclosure. The O2+ODAC sells at just $285 which, performance considered, is a bargain. We test whether this amplifier and DAC combination is really the giant slayer it is made out to be!

http://www.techpowerup.com/reviews/JDSLabs/O2_ODAC/