I am coming from a Fiio e11 which is a powerful little amp and this is an amazing upgrade. For this review my set up is a 6th Gen Nano with an L9 to the e12 switching between a pair of UE Superfi 5eb and ultrasone580s (I cant wait for my XB1000s to come in to really see how well these two can play together). The best way to describe the sound is that someone took the mids and highs and threw them all the way to the other side of the room while leaving the bass intact. The clarity and separation is greatly upgraded from the e11 I would rightfully say...