BAT Vk55se or Atma-Sphere S-30 MK111 withal all the upgrades ?

There is an 8 ohm version of the DI, which is the one to use with tubes in general.

Hi, you may be interested to join this facebook group for Tekton Design speaker owners in case you have questions or would like to know more about their first hand experience with them, and the electronics they use to match with their speakers:

https://www.facebook.com/groups/135142323767796/

I think Tekton offers an 8 ohm version which might suit tubes better.

I think the Atma-Sphere would add more speed, more transparency and larger sound stage, all of which I am told the Tektons excel at. 

Jim
Not a dealer for any of the mentioned products but have experience with the amplifiers.

@blindjim thank you for your thoughtful response about each of these amps. I have made the decision to go with the BAT because A) brand synergy, B) The Atma M-60 monos, although beautiful and detailed were slightly thin in areas, less body, or"meat on the bones" as they say. C) Less fussing around with tubes and fuses, and of course this was the S-30 so even less power there. I think both companies are great but so far I like the overall sound of BAT and I am hoping that the 55 has nice transients, open space around instruments like the M-60 but with more weight. HA, we will see . 
Best, Greg

@greg22lz

Tuff gig.

I’ve owned BAT pre and amp. Mine were the VK5 pre, VK500 SS amp. Later, a VK 60 amp. Still later, I replaced the BAT pre with a Thor Line stage. And ran that with the BAT SS amp as I enjoyed that pairing best with the speakers on hand at the time.

Many will say the synergy of having same same branded power is best. Others will disagree. I’ve found both ways work well. In fact both directions will yield great results depending on the quality of the gear itself.

At face value, I would think both of your options will work with the speakers. Usually, lower power offers a bit sweeter sonic.

I would call both BAT and Atmasphere and ask them about their respective amps qualities you may be unclear about.

Both should do quite well. The issue here predominately is which sound you will like best.

As I’m unfamiliar with the speaker specs, I would ensure the sensitivity of the Tektons is adequate enough, so you will be able to obtain the volume levels you desire in your room with the 30 wpc Atmas amp, should you go that way..

The BAT amp with a touch more power, should easily fulfill that job.

If everything fits power and speaker wise, and all else is equal more or less, age, condition, & price, I see this as a coin toss. Each brand is a quality piece IMHO.
Best of luck.