I don't hope all that much for a 50mm CNT driver, but for a better constructed headphone with the S500 one. I feel that both the s500 and s400 weak points are in their design and construction quality. As well, I don't know if I could stand more bass and more highs than I am already getting. More quality in that sound spectrum I could use for sure.
As soon as my wallet get's a rest I will try these S770.