Tube amp recommendations to drive Joseph Audio speakers

Looking for a tube amplifier to drive my Joseph Audio Pulsar 2 Graphene speakers.  Preamp in the system is an Audio Research Reference 2 Mk II, cables are full loom Zavfino.

Have been using a Pass XA25, but while detailed and clean, the sound is just a little too yin (lean) for my taste.  Want a little more tonal color, density, and bloom to the sound.

Hope to stay around $5K new or used.

Thanks!