Hey jaudio1,
No problems driving the 20 Signature speakers with Pass Labs XA-25 amplifier. The XA-25 is one of my favorite amps, I own one, and the match-up is terrific between the speaker and amplifier. The "beefer" amplifier you use the better the bottom-end becomes, such as my Coda #16.0. However, the XA-25 does a great job on this speaker.
No problems driving the 20 Signature speakers with Pass Labs XA-25 amplifier. The XA-25 is one of my favorite amps, I own one, and the match-up is terrific between the speaker and amplifier. The "beefer" amplifier you use the better the bottom-end becomes, such as my Coda #16.0. However, the XA-25 does a great job on this speaker.