About the Ep-630, A review says as " Its higher audio range 6 - 23000 hz (most others are in the 20 - 20000 hz range) also contributes to its sound quality. I could hear some part of the music more clearly, which were not pronounced when heard thru other headphones. It also doesn't have the irritating thumping bass that Sony and Sennheiser usually have. So, one hears the natural sound as it was recorded, without making all music like "remixes" with huge thumping bass. I am very satisfied with this product and would recommend to anyone who enjoys music." - I think, it is a good one.