I use ATH-M50s (over ear) and shure s115 (in-ear). Both sets sound great to my casual ear. The ATH-M50s work best when my surrounding area is quiet. If someone is talking I can't hear what they say but I can hear muffled sounds. The Shure in-ear buds are fantastic in isolating you from external sounds. I relied heavily on head-fi.org for guidance. If you are thinking of full size headphones go to a music shop and see if they'll let you try on different pairs. I found that the Shure over-ear pairs felt heavy and uncomfortable, so I went with the ATH-M50s. Also I do not use any external amp at work for either pair, just straight plug in to the stereo out on my machine.