Given that the T2 has been mentioned recently, and, given its scarcity, I would like to say that I am completely intrigued. If one of you has one and you're thinking of parting with it, please let me know.
I’ve used the STAX SRE-925S extension cable (same silver plated stranded copper as comes stock on SR-009/S) on occasion between my old KGST and KG GG and STAX SR-003mk2, SR-207, SR-L700, SR-007mk2, and SR-009.
Basically the cable adds some extra capacitance to the headphones for the amp to drive. The higher current KG amps will drive the cable OK, but with lesser amps the sonics will suffer some. With my KGST (@10mA) and SR-007mk2, there was some minor degradation in direct A/B comparison with and without the extension cable. With my GG (@20mA) and SR-009, I would not bet money on me hearing a difference when I did the same test. IMO, with your Carbon (20mA) and SR-009S, SQ using the extension cable should not be a problem to worry about.
I’ve got a SRE-925S in the hall closet I’m wanting let go. PM if interested.
Where abouts are you in Washington State? I’m in Vancouver.