Does It have to be loud?

I am with the crowd that thinks the ability to sound good at lower volume is a high priority.  Yes, the ability to play at high volume is a criterion of performance, but, the ability to sound dynamic, full and exciting at low volume is more important to me.  I know one can show that classical music has an enormous dynamic range such that the peaks can be well over 100 db.  But, recordings don't come close to delivering the full dynamic range; if you set the peaks at 100 db, the quiet passages are unrealistically loud and inappropriate.  I don't ever play such music at "realistic" peak volume.  For amplified music, I don't ever want to attempt to duplicate a live performance; frankly, if my system only sounded as good as perfectly reproducing such performances, I would dump it.

The very best systems at sounding good at low volume levels also tend to ones that are highly efficient and easy to drive.  That allows the use of low-powered amps.  That is a really big deal to me because ALL of the amps I really like happen to be quite low in output (the most powerful is a custom-built OTL amp at 30 watts).  I haven't heard most of the high-powered candidates out there, but, I've heard a few and they have the same problem--they sound dull and lifeless and un-engaging, particularly if you don't crank up the volume.  

David,

The amps I have liked the most are tube amps.  I own a custom-built push-pull 45 amp, the Audio Note (uk) Kageki (parallel 2a3 SET) and a custom-built push-pull 349 amp.  The Kageki, rated at 6.5 watts/channel, is the most powerful of the trio.  But, I had in my system a solid state First Watt J2 for about two weeks (borrowed from a friend).  The J2 sounded very good--it was vivid and engaging and only a touch hard on the initial attack of notes. I could easily live with the J2.  That same friend built for himself a low-powered SIT amp based on schematics made available by First Watt.  I think that this is also an excellent low-powered solid state amp. 

In the past, the common complaint raised against solid state is that the sound tended to be harsh and "grainy."  I don't think that is the case these days.  Most solid state amps are smooth sounding and are not at all unpleasantly harsh or shrill.  To me, the complaint about harsh and shrill can more often be leveled against high-powered tube gear than solid state gear.  But, when even decent sounding solid state amps are played at the lower levels I prefer, they sound a bit lifeless, and I tend to lose interest.  A friend of mine, who also loves low-powered tube gear, and who has heard much more stuff than I have (he goes to the Munich show), says that the Bridge Audio Laboratories (BAlabo) high-powered amps sound good.  I have not heard these amps, and in any case, I could never afford to buy amps that cost six figures.

han_n,

I have heard the Tekton Double Impact (not the SE version) at a recent audio show.  I really liked what I heard; certainly a great bargain at its price.  I bet the SE version sounds even better.  I don't recall what amplifier was being used.  At 99 db/w, these speakers can be used with very low wattage amps, particularly if the speakers are played at reasonable levels.  To me, it is more of a bragging rights kind of thing that a speaker can play at 115 db--I would not want to listen at that kind of level (like owning a road car that can go 220 mph).

While I have stated a preference for tube gear, particularly where one can get by with modest amounts of power, I certainly expect that good solid state gear can be quite satisfying.  I have not had that much exposure to Pass amplifiers, but, the First Watt amps I mentioned that I really liked are designed by Nelson Pass.  The First Watt gear is aimed at a particular niche market--high efficiency speakers that present an easy load to drive.  I like your choice of the lower powered model from Pass' lineup.  I once auditioned a 50 watt solid state amp and a much higher-powered model from the same manufacturer (both very similar in design) and preferred the lower power model; it might be use of fewer transistors operating in parallel that made the difference (I hear the same thing with using multiple tubes to achieve higher power output, the result is not good).

Most of the better brands of solid state gear deliver decent performance.  There is a sameness to the sound of solid state, including Class D, that makes it actually hard to make a terrible choice.  That is not the case with tube gear.  There is much more variety in sound with tube gear and that is both good and bad--good if you carefully choose what works with your system and taste (or get lucky), more likely bad if you don't carefully audition and choose wisely.  A lot of even "bad" (to me anyway) tube gear will still deliver the rich sound and enveloping soundstage that is the most obvious characteristics of tube gear, and one can easily, at first, miss problems in other areas of performance.  It takes more experience finding the right tube gear choice.

I should also mention that, I also like the Ayre brand of solid state electronics.  For Class D stuff, I have heard decent sound from Bel Canto amplifiers.