Looking for new speakers for large audio room

Common clearthinker, why not!

Given you amplifier's power I think  Atma sphere's recommendation makes the most sense. Without a line source dipole I think horns will work best. However, with subwoofers your amp will drive Sound Labs 845's but you would need two more subwoofers for it to work really well.
I use JC 1's which are Class A to 25 watts and I rarely use more than that. I also believe your Pass will push a lot more power just not in class A.

Hello,
+1 for the extra subwoofers. If you are not going to go that route I would go with one of the KEF blade 2s. They have side firing woofers that creat a ton of bass. If you don’t believe me go listen to a pair in a room half the size. These things need breathing room and you have it. Also, with such a big room you want the music to sound good outside of the perfect listening chair. These do it in spades. I love the KEF Reference 5s. You would be better off with the blades. KEF has a subwoofer, The KC62 that plays down to 11hz in a one foot square box. It’s like having two of these awesome subwoofers in each speaker. I don’t own KEF Blades but I have heard them at a brick and mortar store close to me. https://holmaudio.com/This store lets you try stuff out in your home on your equipment for free. No buyers remorse. I hope this helped you out. 

Here is a good list for you:

KEF Blades - Gershman - Dynamakkit - Vivid - Estelon - Ascendo - GT Audio in New Jersey - Vandersteen the new model sevens mark IIs are coming out shortly

Happy Listening

Tannoy Canterbury

Most of the speakers brands most of you recommended aren’t being sold by any local dealers in Thailand

Due to the size of your room unless you have a very high powered amp horns of some sort are probably in the mix. So do you plan to only work with speakers that are available through dealers in Thailand? This sounds very tricky any way you look at it!