What tube amp for Harbeth 40.1


I am looking for a tube amp for Harbeth 40.1.  I know many suggest SS amp such as Accuphase, Luxman, Hegel, McIntosh ... etc for Harbeth, but I decided to keep it with tube.  I also don’t think I need a lot of power.  I currently have a 8W custom built 300B and had a 18W Almarro 318B, and to me, they sound fine.  However, I think more power will help, and I never know what I missed until I try it out.  Having said that, I don’t think I need crazy power.  Anything 30-80W is good enough for me.  I am 3m away from the speakers, listen to Jazz at avg 83dB.

i have the following short list:
1) PrimaLuna Evo 400 integrated
2) Leben CS600X 
3) Linear Tube Audio Z40

Which one do people like with Harbeth?  Any other suggestion?

Among all qualities, I value holographic presentation the most.  I really like the feeling as if the singer is floating in front of me, if you know what I mean.  And my current 300B do pretty well in this regards, and I read this is what SET amps are good at.  Will I be disappointed with the above?
Thanks.
gte357s
@squeak_king_77Thanks for your feedback on Leben.  Based on that, it seems the CS600x may not be suitable for me.  For example, compared to the Almarro and my custom built 300B, I feel the Almarro is more “linear”.  I don’t know if this is the right term.  I feel my 300B is a bit more dynamic, more engaging ... hard to tell exactly what are the differences, it is more a feeling and impression.


I heard good things about atma-sphere.  But  ... it takes many tubes, it would add to the cost.  I am not sure how expensive are the tubes ... 
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Probably a long shot.  Anyone has experience with Luxman mq-60?  It is a vintage in 1970s.  It is a push-pull in triode mode.  It originally use 50CA10, but I am going to change it to 6L6.  It outputs 30W.  I know 30W is likely not enough, but just think to try based on the price tag.