iFi iDSD BL DAC + Headphone Amp Review: Black is Better - The Sound Apprentice
Review and Measurements of ifi nano iDSD Black DAC and Amp | Audio Science Review (ASR) Forum
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 nano iDSD Black Label Portable DAC and Headphone Amplifier - Retrotone