The problem with uber expensive amps is they often have something to prove. They try too hard to be stand outs and therefore have a heavy signature on the sound.
Instead of looking for differences based on price, I suggest you listen to a few distinctly different amps:
- McIntosh
- Ayre
- Luxman
- Pass
- Parasound
- D'Agostino
- Vandersteen
Two or three of those sound very very good and close to each other, and the rest are going to give you a remarkably different presentation. Is the most expensive the best sounding? I have no idea, but there's a couple of really pricey brands on there I wouldn't have in my house, even if off for fear they'd corrupt my listening experience. 😂