- May 20, 2003
Several years ago, when the HD-650 came out I had the same problem with clamping. Over time they did loosen up. When I got them refurbished by Sennheiser I got the clamp effect back. Recently, I purchased an open box from Headroom Headphones, and did not have the clamping issue at all. I don't know what is up with that, but the HD-650's are worth the time and effort to get them tuned in to your head.