Maybe you know the reason of the problem, it is driver itself or some internals design? Seller says that they were in Beyer service for driver replacement, drivers definitely should be recent one i think, so would this mean that signature will be "fixed", also it is interesting do beyer do some serious after service test (as i know no freq. response graph was included after repair).
T1 is not a cheap buy, so i try to figure it out as much as possible...
I guess there was a problem with the drivers but I'm just guessing.
Not sure if I'm following you.
Are you planning to buy a second hand T1 that was sent to Beyer service for driver replacement?
If that's the case, were both drivers replaced?