pass x350 vs. plinius sa 250mk4.

plinius is great

Pass is better than Plinius and should be a perfect match for Extrema...that's what they need
a strong solid state amp. You can also give it a try to Jeff Rowland 8Ti...but at much higher cost .Good luck

Tough Call! I ultimately narrowed my own search to these same amps. The Pass finaly won out, but mostly due to non-sound related issues. Pass (Built in States and very accessible), Balanced design working extremely well with balanced Line stage (Also a Pass), and not a full time Class A design therefore saving some power and heat (I leave my components on full time.)

As for sound, they're both outstanding, but I believe the pass edged out here as well, particularly in HF extension and transparency.

Good luck.

Good luck