These are my second pair of Audio Technica headphones. I also have the ATH-AD700 which I really do love. But I can't use them at work because they drive my co workers nuts. I leave my music on pretty loud, and with the open air dynamic design, they leak a ton of sound. These are sealed, so they work for work :). I have heard great things about the ATH-M50 so I purchased these. Every good thing you read in the reviews are true!!! These really are AMAZING. AT is #1.