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

I'll go as far to say it's not the tube amp but rather your choice of tubes. Vintage little Mullards are extremely warm sounding. Vintage Tung Sol 6550's solid plates are warm like Mullards but with the EL34's glorious mids that are known for but with a lot more low end and power. I was never a fan of current production tubes. I had the Octave V70SE and later the V110 with a black box. I even had the V40SE for a short while. All were good but as you move up the line you gained more 'control' of the music.

@drumbeatCongrats on the Joules!! Curious what type and brand of output tubes does it comes with? I ask because I've seen replies stating 6550 - KT88 etc (myself included). When I mentioned TS 6550 solid plate vintage I did because they are very warm sounding. SED 6550 on the other hand are very linear where the SED KT88 is very warm. Vintage GEC KT88's are also a very linear and clear sound. Current production Gold Lion KT88 are in the middle leaning slightly leaning toward a linear sound. What I'm trying to say is you can't state a type of tube (6550/KT88) has a specific sound characteristic.

@signaturesound
Guess I should have looked at the specs for the amp first but at least I got share my impressions of some of the different output tubes I have.