Whats the FATTEST sounding Tube amp to warm up Lean speakers?

Ah...just noticed dumbeat already made his choice.
"never mind...." ;)

Joule amps have been called many things, but lean is certainly not one of them. They would add what you are looking for, in spades, while also preserving solid bass, and dynamics. 

I bet CAT amplification would sound great with Merlins

@tzh21y CAT amps do sound great with Merlins. I have heard the combo several times (Merlin and CAT demo’d Together at shows HiFi shows in the mid 2000’s) and I know of at least one VSM owner off the top of my head who has CAT amp on his Merlins.

Joule Electra OTLs also sound pretty darn great on Merlins too (you are right @nightfall certainly not lean) :-) I know there are plenty of folks out there still using Joule gear on Merlins.

Rich

Hey Joneil, thanks for that update! As from others as well, the Music Reference are next on my on my radar if ever again the itch rears it’s head. Love my Quicksilvers for now and possibly ever as it seems you are with your RM9s, ain’t life grand!

Roger, David Berning, Ralph Karsten and Mike Sanders have been at this for decades, dilligently improving their designs with  each personally involved. This is what I place value on when considering any audio product, personal committment from the owner/designer.