Warm Sounding Speakers

Tannoy get the prestige series add a super tweeter.
Kef are warmish but it depends very much on the model these days.
Big Vandersteens.
Quads (very polite not terribly dynamic)
and the Harbeths which I find very warm and not my style of speaker but you might.
Ditch the Krells and get the New Carver Monoblocks with new or old style tube sound. The old style may be what you want.
OK I am ready -flame away. I personally like detailed speakers and modern tube sound.

Other tweaks that warm up sound. If the tube buffer is an option then choose the 6SN7 based ones like the Grant Fidelity recommended above. Warm 6SN7s are still likely to be truly the best if NOS. The RCA Red Base 5692 tube wj=hile expensive is warm as are other 5692 s which are drop in subs for 6SN7s. Add Ken Rad 6SN7s GTs to the list as well. Although wildly expensive the Brimar Black Glass Brown Bass CV1988 is an incredibly good 6SN7. The cheapest of the lot of warm 6SN7s IMO of course is the Green Label Sylvania GTBs, the various other Sylvanias are good to great but not as warm.
The next trick is to use good Copper IC and Speaker Cables. The warmest in my mind is the Cardas Golden Refs, expensive you'll prolly have to buy used. Look for Cardas anythings with Golden in the name, I am not joking. Also Jena Labs but even the entry level stuff is expensive.
You could just buy an older CJ pre amp for less and get warm sound that way.
Rembember tube power amps are your best bet in the end, I just don't advocate ARC for warmth they are clean crisp precise and defined (it's in their slogan.)