With the Ref2 MkII you can tube roll the rectifier (5AR4) and power regulator (6L6GC) tube. I haven't tried swapping tubes on my unit yet as the stock tubes sound quite good.
I also don't find the Ref2 MkII "bright" per se but it is quite precise and 'neutral'. It seems to get out of the way of the signal and yet imparts a pleasing flow and musicality. I've heard the LS2B and LS5 MkII; these older units do exhibit more traditional tube bloom and warmth.
I also don't find the Ref2 MkII "bright" per se but it is quite precise and 'neutral'. It seems to get out of the way of the signal and yet imparts a pleasing flow and musicality. I've heard the LS2B and LS5 MkII; these older units do exhibit more traditional tube bloom and warmth.