I did some research online before making this purchase. I wanted to get some headphones that had plenty bass for the best price. These Sony MDR-XB700's deliver that. I ordered them and the FiiO E6 at the same time. The XB700's came a few days before the E6, so I had a couple of days to get use to the sound before the little headphone amp arrived. When the E6 arrived, I couldn't believe the difference. This is a great combination. I have bass in my headphones for days.