I was lurking over on Amazon's Electronics Gift Guide, and I happened upon these pairs of headphones. They just came out at the beginning of October; there has been some sporadic discussion about them here on Head-fi. They are supposed to have "LiveStage" technology, which is accomplished via two AAA batteries on the S500 or a built-in rechargeable lithium ion battery on the S700. I am doubtful that this is another gimmick. Hopefully not, considering JBL is in the Harmon/AKG family.
This CNET review by Steve Guttenberg gave some insights on the S700's: http://news.cnet.com/8301-13645_3-57606553-47/jbl-synchros-s700-a-bass-lovers-headphone-par-excellence/
In addition, these Amazon reviewers seemed impressed by their build quality and sound:
Anyone give either the JBL Synchros S300, S500, and S700 an audition yet? Thoughts?
Edited by Soba - 11/11/13 at 9:24pm