From my limited experience I thought the X250 sounded better than the X350. When I contacted Pass in Oct. 2004, just before the release of the X350.5, Peter said the X350 was not their best sounding stereo amp. He also mentioned at this time that out of the new .5 series amps the X350.5 was at the top of the heap. He has it in his own setup in his home.
I did purchase the X350.5 after my conversation with Peter Perkins and would agree with what has already been said about this amp. I used it with Thiel CS2.4 and the X600 with Thiel CS 7.2. As an experiment I tried the X350.5 with the big Thiel's and preferred the X350.5 over the X600. The X350.5 gave up a little in the bottom end, and I say a little, over the X600. However, the midrange and top end with the X350.5 was clearly better. The music just flowed and the top end was silky smooth.
Regarding the X600.5 I would like to hear from others who have auditioned this amp.
I did purchase the X350.5 after my conversation with Peter Perkins and would agree with what has already been said about this amp. I used it with Thiel CS2.4 and the X600 with Thiel CS 7.2. As an experiment I tried the X350.5 with the big Thiel's and preferred the X350.5 over the X600. The X350.5 gave up a little in the bottom end, and I say a little, over the X600. However, the midrange and top end with the X350.5 was clearly better. The music just flowed and the top end was silky smooth.
Regarding the X600.5 I would like to hear from others who have auditioned this amp.