David: you are correct, which is exactly what I wrote in post: The INT-150 is class A/B, but runs in class A for first 30 watts (it runs pretty f-in hot) which is more than enough for the Nines. My intuition tells me that the new Pass integrated, the INT-30A (which is based off of the 30.5 amp, pure class A) would be a better match, as you don't need the kind of power the INT-150 has (150 WPC) to drive the Nines. I've heard the Nines with Shindo, but not for longe enough to make a judgement. I heard them recently with the luxman 509A II, which is 30WPC pure class A, and both I and my friend who is buying the nines thought it sounded stunning.
Other amps that I know some people, including John, have mentioned with the Nines include Pathos, Leben, Shindo, and YBA. Like with anything though, they need to be broken in before you know what to mate them with.
Other amps that I know some people, including John, have mentioned with the Nines include Pathos, Leben, Shindo, and YBA. Like with anything though, they need to be broken in before you know what to mate them with.