I think your quest is contrary to the current trend in PP tube amps which is warm toward neutral with a better dynamic range and tighter bass. Syrupy is considered a fault these days. I think of "bloom" as the good side of syrupy.
I would suggest a Dynaco ST-70 or the like for the sound you seek with some wattage.
If low power is OK there is always 2A3 or 300b designs with great midrange but rolled off highs and flabby lows.
I would suggest a Dynaco ST-70 or the like for the sound you seek with some wattage.
If low power is OK there is always 2A3 or 300b designs with great midrange but rolled off highs and flabby lows.