I just got my T1 2nd Gen headphones today. Just had a quick listen and can compare the handling to my previous beyerdynamic Amiron Homes. The T1 2nd Gen feel less substantial and lighter than the Amirons. Now this is quite odd as the spec sheets suggest that the T1s are heavier (Amiron Home = 340g without cable, T1 2nd Gen = 360g without cable). The Amirons have plusher coatings. However, the handling of the T1s feels better to me. I find them more comfortable on my head. The cable is also lighter (but is stiffer) compared to the one supplied with the Amirons.
The Amirons are a LOT darker and have less treble. The T1s sound a fair bit more sparkly with a more pronounced upper end. The sub-bass on the Amirons is superb and is a little light on the T1s. For example, there is the starting of Soul Embrace by Brian Simpson on the album Just What You Need that has a bass drum thump that was simply incredible and breathtaking to experience on the Amirons. It literally felt like someone hit the underside of my skull directly, such was the sharpness and intensity of it. That track is my reference track for sub-bass. The T1s don't quite hit the mark with that track as the Amirons do. I'm hoping the sub-bass improves with more burn-in.
The clarity with the T1s is an improvement over the Amirons. I can't comment on soundstage yet as I haven't spent enough time listening to them.
They'll be undergoing a burn-in for several nights. Can anyone recommend a burn-in time for them?