Flyfisher: Your mentioning this reminded me of something i overlooked in my previous comments in this thread. My Father REALLY loved when i brought over a Nelson Pass built & designed amp for him to use. It sounded very sweet, airy, delicate and liquid within his system. I remember him saying that it was the most impressive amp that he had ever heard, but he was disappointed in the lack of "oomph" on the bottom end. This was prior to me modifying his speakers, replacing the speaker cabling, changing preamps and swapping out interconnects in his system though. In effect, he had a very different sounding system than he does now.
As i've commented in the past, i've never found any of the Pass designed amps to have "bottom end wallop" that some other amps deliver. The bass does sound very "natural" even though it lacks "slam" and "impact". The newer .5 series of amps are supposed to address some of these areas and there is no reason that you couldn't impliment some of these changes / parts upgrades to the existing X250 that you have. Either way, you have a very nice amplifier as it is and i'm glad that you like it.
I would look carefully at the cabling that you use between the amp and the speakers. This can really make a huge difference in my experience, regardless of those that say that speaker cables are all the same. Making sure that you also have a 20+ amp circuit to feed the amp and a good quality power cord will also add a bit more icing to the cake, which may be all that you're looking for. Sean
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