@russ69
1- I do have tubes in my headphone amp
2- I used to run a tubed system- I had a Conrad Johnson pre amp (17LS2) and amp(M60SE), and a Rogue integrated (Tempest Magnum II) and once I turned to Pass, I found that I no longer had any yearning to drive my speakers via tubes
For me with the Pass gear, no tubes and I'm off the circuit are not incompatible!