Looking To Match A Tube Amp With A Pair Of Audio Note AN-K/Spe

I've seen and heard the Backert gear at audio shows.  It is hard to make a sonic evaluation of electronics at a show, but, I did like the very serious people designing and backing the product and I liked what I saw.  You  indeed should be looking at a power amp, and something from Audio Note is certainly a good place to look initially.  While the K's are not in the extremely efficient category, they are fairly high in efficiency and are easy to drive and anything Audio Note offers should be in the running.  I have not heard the Empress, but, I do own, and like very much, its sibling; I own Kageki monoblocs (parallel SET 2a3 amps).  The Kageki's are slightly on the leaner sound side of the Audio Note family of amps, but they are among my favorites.

Thanks Larry, I'm also intrigued the Level 4 EL 84 kit that's available. Seem's that might be a good match for the K's in a 30x12 room. I listen primarily 8-10 feet away with proper toe in.  -Scott

If you are talking about an AN Kit amp, I don't think they are affiliated with Audio Note (uk).  They have put together similar gear based on Audio Note design and buy those parts that Audio Note  offers to the market, but, that does not mean they are as good as the real deal.  They may be a good bargain, but, that is not to say they are the same.  

Still, I generally like good EL84-based amps because they are lively, and punchy without sounding hard and brittle.  I prefer that tube over something like a KT88 or 6550, KT120 or KT150 or other more powerful tubes.  Some EL 34 amps are decent, but, generally, I prefer 6L6 or KT 66 the most among pentode/tetrode tubes in common use.  There are exotic types, like 350B and th3 349 that I like even more, but, those are extremely rare and expensive (I own a 349 pushpull amp that puts out a whopping 5.5 watts per channel).

Among low-powered triodes, my favorite is probably the 45, but, it is a very low-powered tube; that tube would be followed by the 2a3.  

If you had to choose between a push-pull EL 84 at say 20W or an SET 2A3 say at 8W to push the K's what would you prefer?

Not that much to go on, but the safer bet would probably be the EL84 amp.  My 6.5 watt Kageki (parallel 2a3 SET) amp is enough, for me, with my 99 db/w speakers, but, I don't play my music that loud and on some music, the amp does seem to loose a bit of steam (doesn't really distort, but it stops getting louder).  My speakers are considerably more efficient than the AN-K speaker.  The issue is whether you prefer the sound of the 2a3 when playing the vast majority of music, and if so, how much would you be willing to give up on the capability to play very loudly.  I prioritize good play at very low volume level myself, and the Kagekis deliver on that score.  For the record, I currently run a pushpull 349 amp that I actually prefer to the Kagekis in my current system; both are good, the 349 amp is a bit richer sounding and is a touch more dynamic.