It's all I need

Most IEMs I own do not benefit or need an amp. A few do. The bass boost is just what my sonic taste needed from my RE 0 and Carvins. My Sansa Fuze needed a boost when I listen to my Sony headphones which was my main reason for the purchase. My Sony Walkman benefits from this amp as does my Cowon J3, the latter by the bass boost function. The build is first rate. It's an amp, it amplifies what needs amplifying. If there's junk you get louder junk, if it's clean than you get clean. It changes nothing from what's there and I think most people will appreciate the improved bass option at a budget price. JDS guys are all about help and service, I couldn't be more satisfied. I've had amps at three times the price but this is the one I'll hang on to.