the smoothest sounding speaker

I would suggest you check out Daedalus Audio. One of Lou's key design objectives is NO listener fatigue. I had the DA-1's for a couple years and they were the most non-fatiguing (yet lively and dynamic) speaker I've ever owned or heard--and I've owned several of the speakers mention such as Harbeth Compact 7's, Spendor SP1's and Spendor S100's. I've also heard the Aerial 7B's. If non-fatiguing sound is your thing, the Daedalus stuff is worth checking into. BTW, Lou is going to release several new models at the RMAF in a few weeks. He has two new "Reference Line" speakers and will be rolling out updated versions of the excellent DA-1 and DA-2. One of these models will be gracing my living room shortly. If your planning on being in Denver, go have a look.

I hate to argue with you Lou but in my experience it is the loudspeaker that is most often to blame for fatiguing sound. Before I found and fell in love with your DA-1's, I heard countless speakers--most often connected to top shelf electronics (both tube and solid state)--and often found them to wear on me after a relatively short period of time. There are very few speakers out there that get things so right that you can listen (at volume) for hours on end and never feel oppressed. I'm not saying that poor electronics can't mess up an otherwise good speaker but for the most part I think you need to get the loudspeaker right first and foremost. I think your success in this area transcends choice of electronics and source components.