iFi audio Micro IDSD Black Label - Portable DAC/Headphone 303014
iFi iDSD Black Label: Swiss Army knife utility, top tier sound and flexibility that does everything extremely well, so much value it's just unfair to the competition – Audio Primate
iFi Audio micro iDSD BL DAC and headphone amp
Review of iFi iDSD BL | The Headphone List
Review and Measurements of ifi nano iDSD Black DAC and Amp | Audio Science Review (ASR) Forum