Some people posting here claim that efficiency is a mark of performance in loudspeakers so here is a fact to consider.

Audio Note's most efficient speaker and best design is the E series which has a rated sensitivity of 94 db.* Klipschorn has a sensitivity of 104 db.

http://www.klipsch.com/product/product.aspx?cid=2

That's ten times as efficient. If efficiency is what is important to you and the way you judge the quality of a loudspeaker, then there is no comparison. By this standard, Klipschorn blows Audio Note and just about every other speaker away. What's more, Klipschorn is probably as cheap or cheaper. Able to handle 100 watts RMS and 400 watts peak it can put out up to an ear shattering 121 db. It's range is alas only rated on the low end to 33 hz but that's at 3 db down not 6 the way Audio Note's is so they are slightly closer than they appear with A/N E rated at 18 hz. Of course there is the size. Klipschorn is a big boy. Audio Note E is an oversized bookshelf model. Klipschorn wants the corners although they have other models which don't. An probably should be mounted on its dedicated stands. Klipschorn can fill an auditorium with ease. What can A/N E do? I don't know but just looking at it, most likely it's no match there either.

*based on A/N specification of sensitivity for E; level 1, 2, 3 = 94 db, level 4 E/SE=94.5, level 4 E/SE Silver = 93.5
http://www.audionote.co.uk/

Conclusion, people in glass houses shouldn't throw stones. When efficiency is the criteria, there's far better than Audio Note and most others as well.