I just recently purchased a pass labs int-60 I love it works great everything but be warned they do not work well with ohm Walsh 2
The Pass is just manufacturer spec'd at 60w, but it's got good current as it can get to 200w into 2ohms, so the problem to me is not enough watts.
As the Ohm Walsh 2 is said to be not a hard load at an average 6-4ohms.
But it's only 81db!!! efficient, you just simply clipped the rails (wattage).
From hifi classic "We measured a sensitivity of 81 dB"
Bet the Pass sounded good right up till the fuse popped though. I'd change the speakers.
Cheers George