If I read the description without reference to equipment, I'd say you're looking for Beethoven rather than Tchaikovsky.
Since you've tried and (apparently) opted away from neutral and accurate preamps that, imo, don't get in the way of music's dynamics, timing, and tonality, its hard to gauge what is missing from those units that you hope to find. Can you say what is the amp that represents your sonic goal?
What music do you prefer mostly?