I purchased the HD 600 after having the HD650, the AKG K701 and Beyer Dynamic DT880 600 ohm. The HD600 is a pure réusssite. The most balanced, the most transparent, the most articulate, the most musical of all. The controversy raged between HD600 and HD650 and I hesitated between. I opted for the HD650 saying he was newer so best. Yet, just the fact that the question whether the HD650 is veiled or not said enough for departing ... To my ears, the HD650 is a regression compared to the HD600, to have a sound more glue to the standards of the time: the focus on the serious and softens up. Finally, the HD650 produces a pleasant but too far. While the HD600 focuses on music and is forgotten ...