The Absolute Sound and also Nuprime, in a follow up, found the STA 9's not a good match for LS50 due to brightness. I am using STA 9 with Sonus Faber and hear no such brightness whatsoever.
Have done a bit research on the LS50s so-called 'brightness' and users have found using tube amps resolving the 'problem' hence the decision to use the STA-9s for their 'tube-like'/warm sound. I notice that the LS50s are very sensitive to cable selections, most noticeably from my recent switch from Audioquest FLX/SLip4 to Telerium Q Blue, where the mentioned 'brightness' was most noticeable ( too much tech i guess in the combo
Was considering tube-amps i.e. Primalunas, Unison Research, Bob Carver Black Magic, etc ( surprisingly it 'gels' with these so-called 'low-wattage' amps) but personally don't like the hassle that comes with it, hence again the STA-9s.
As for the SCM 11s, I love the 'naturalness' of its presentation esp. with timbre instruments whilst the LS50s its 'preciseness' esp. with progressive house music and both do well with female vocals, albeit in their own personal way. I tend to alternate usage, depending on my mood.
As mentioned, I am in need of more 'grunt'/power to get the best of of both speakers ( they 'breath' way easier/dynamically, with the extra power as reviewed)