This is new to me. Is what you're saying based on own experience or repeatedly mentioned somewhere?
It's been going around for a while amongst T1 Gen 1 owners. I've spent quite a while researching the various iterations of T1 through the serial numbers, and there is definitely solid evidence that the product is being updated both physically and sonically though its lifetime. As far as I can tell, my S/N T1 is definitely better sounding than the older S/N (around 4000 iirc) that I had the opportunity to use for various purchase auditions.
Interesting. I must say I never delved deep into the T1 thread or outside HF. This ''evidence'' of sonic changes is described by numerous posters in that thread I take it?
Could you also very briefly sum up the changes physically and sonically?