If you are a classical music enthusiast - AVOID these units.
The AF45 has a good mid range nice and clear and a firm bass. The higher range though is a complete disaster.
Typically the higher notes of organ music are tainted with distortion sounding like an annoying accompanying whistle. If you want to hear your favorite opera singer hitting the high C's - -forget it, it's utterly destroyed by the accompanying distortion(whistle).
I have compared the AF 45's on laptop and mp3 players with the identical music on my Sennheiser PXC 300's - no whistle, Shure E215 very little colouring only just perceptible. Even the buds that came with my Creative Zen xFi had little colouring on the upper registers although not as good as the AF 45's in the mid or bass ranges.
Made a big mistake with these - last audio purchase I make online without trying out first.