I have always been surprised so many people consider the T1's bright. Maybe I got lucky with mine but there is no excessive brightness with the Woo6se, Audio-gd Roc or balanced out of my Audio-gd Master-6.
I know they have that 'peak' (8-10khz if I remember correctly) in the highs but I have read before that apart from cymbals and some high pitched vocals very few other instruments play in that range.
In comparison to my other phones, all balanced on the Master-6, the T1's are only slightly brighter than the HE6's and the HE6's are also fractionally brighter, on some but not all disks, than the LCD2.2 with Twag silver cable.
Well, we don't all hear with the same set of ears. In my case I was sensitive to that peak in the 8-10k area but it only showed up on some recordings not all. It appeared as a slight edge on recordings that had harmonics in that region. A little eq fixed it for me so I don't even have to think about it. I see some folks actually modding their T1's to arrive at the same effect which I think is a little excessive. Just a modest 3bd cut in that range did it for me. Don't get me wrong, I love these headphones and would not part with them. I have compared them to the HD800 in my home and I kept the T1's. Enough said.