I just ordered a K400 off ebay! I have have a few AKGs and I am excited to give this headphone a try. I think it is one of the best looking cans out there and I am an industrial designer so I tend to be picky with looks. BTW the pair I bought have the rubber headband and I wanted to know if this was added for the later versions and if so how does it sound different from the version with the leather headband?
The one with the rubber headband is the early production.
IMO, they sound the best, with a nice smooth, upbeat sound.
They are more lifely, with a sharper attack, than the later production with the leather band.