Currently at the Stax office in Japan giving the SRM-T8000 a listen - although I've heard it quite a few times at shows, this is the first time I'm listening to it in a proper quiet Stax listening room.
It does seem to emphasise more on the warmth of the SR-009 and take that polish at the top (upper treble) to sound a little more rounded. Coming from a few years of an Eddie Current Electra I actually feel I miss the trebles a little in the SRM-T8000.
The SRM-T8000 to my ears seem to make the SR-009 a little more speaker-like too...so more musical.
I also have the SR-007Mk2 & L700 & I think from a tonality perspective, the L700 & SRM-T8000 are the best match to my ears (again I'll stress from a tonal perspective). The SR-009 will have the edge of resolution of the L700 but the L700 has the edge in terms of tonal synergy with the T8000.
Going back to more listening...
Edit: separation sounds more distinctive on the 009's