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

I don't think you would go wrong with the choice of an OTO.  As to changing coupling caps, this is a matter of personal taste, so be prepared to switch back if the new caps are not to your taste.  My local Audio Note dealer, who also builds his own tube amps and linestages, HATES anything Mundorf.  I have not done any serious comparisons myself, but he has, and does not like them in either amps or speaker crossovers.  He also hates Duelunds.  This is a matter of taste and system tuning, so don't expect any particular change to necessarily be an upgrade, regardless of price and reputation.

Certainly upgraded Audio Note parts should be considered because their gear is voice for these components.  This same dealer has Audio Note parts lying around that are probably worth a small fortune.  Many years ago, I asked about some caps on a shelf and was informed that they were silver foil Audio Note caps that cost north of $1,000 each.   

Thanks Larry. My problem regarding OTO is that I have a Backert Labs preamp which I absolutely love and will not give up. I install the new cables when they arrive (see earlier post) and save up for a few years. I think I'll be on the lookout for a pair of Empress' or buy new when I can.  -Scott

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.