SS goes boom boom boom real loud with lots of watts. The clean, clear, smooth sound of a tube amp is far superior to the irritating harshness of SS. SS gets very raspy quickly while the sound of tubes continues to sound good after listening for any extended period. You can change (roll) tubes for different sounds. You can't change a transistor.
SS vs Tube: What do you hear?
Peter Aczel, editor of The Audio Critic, says "Whatever vacuum tubes can do in a piece of audio equipment, solid-state devices can do better, at lower cost, with greater reliability" (issue 26, p5). What do you hear which causes you to select tubes over ss, or vice versa?