Dear @wolf_garcia : " Ask yourself why most professional electric guitar players use tube amps... Is it OK to like both SS (bad look when abbreviated) and tube amps? I have efficient speakers so I enjoy an excellent tube SEP from Dennis Had, and I rotate in a Pass XA-25 (Nelson Pass likes designing "tube-like" class A stuff) which might be the best sounding amp Pass makes. "
Your speakers are not a guitar, so for me is a uselees argument for tubes in a room/system..
N.Pass " designing " tubes like " SS ". That was a marketing flag because when he was in Threshold his way of thinking was way different.
Btw, everything the same today good class A/AB SS designs outperform the best tube you can have in mind, overall it's just better and like everything " things " change over times. So think today not 5or 10 years ago or even older times..
Regards and enjoy the MUSIC NOT DISTORIONS,
R.