Pass Labs Int 25 vs Int 60

@aberyclark #1 should be easy enough to test.  Find (or make) a quiet track  and just plug your source straight into the J2.  Then compare with it through the BHK.  Or borrow a DAC with variable output and try the same.

As for #2, I haven't heard the J2, but I suspect it would sound quite different from the 25. The J2 and XA25 use different output devices, and a different amplification typology.  The J2 has a SET-like distortion profile with 2nd harmonic dominance and the XA25 has a 3rd harmonic dominant profile (I believe this is true of the 60.8 as well). They likely have different damping factors too, so may interact with your speakers differently.  Only one way to know which you'd prefer.

@shazam Yes, it is my opinion Pass aims at music-first-audiophiles. Those DeVORE Orangutan's will sing on both the INT25 and the INT60. I believe @stevehuff has owned Vinnie Rossi amps in the past, not sure which one(s). Maybe he can comment on this.

@cal3713 one would think if the Pass Labs amps sound great thru Steve’s Klipsch speakers, probably similar with the ZU’s. Thanks for the suggestion. I will run direct dac and see what I hear different. 

with any amplifier selection, fully understanding and properly mating the loudspeaker load to the amplifier capability is paramount for happiness