Dali Helicon 400 or Acoustic Zen Adagio?

Dcstep, I actually found deep harmonic base to be one area that attracted me to the Helicons in the first place. In some respects, the mk1 was slightly better, but there were other compromises that I wouldnt go back to.
I use a few tracks for testing the extreme low bass including Bela Fleck's 'flight of the cosmic hippo'. Or try Sarah McClaughlin's 'i love you' (i think that is the track). Of course some orchestral pieces, and some Patricia Barber is good for this. Not sure what the frequencies are but they are low!
In my experience with quality amplification (especially high end solid state), the Dali's were superior to some of the others speakers in a similar price range. I tried Revel, B&W, Focal, and others.
I find the base a little thick and lacking in harmonics when they are too close to the rear wall, but as soon as you move them away, they come alive. Perhaps you should try this? Maybe it is just the combination of my system and room, and good cables with a tight bottom end also makes a difference. With some extreme high end cables, I got worse results in the base harmonics.

Dcstep, it sounds very much like this speaker doesnt suit your needs and equipment after 5 amps! I must admit I havent seen this issue in my experience with them, but after 5 amps, is it time to switch to a different speaker?

Thanks Mike. I'm using the Vienna Acoustic Beethoven Baby Grand which does everything I need for my current room.

Dave

Sounds like you have a wonderful set up and great speakers. I havent heard the Baby Grands myself.
I listened tonight to some of my test classical tracks eg Prokofiev's Romeo and Juliet and Schubert's 9th, and specifically listened to the deep base harmonics/tonality, and I am still impressed. Must be my set up and room etc. The speakers I listened to before buying the Helicons included Thiel, Revel, Triangle, Dynaudio, Focal, B&W, Elac, Sonus Faber...that i can remember. I also listened to some extreme high end speakers. It took me ages. It is so hard to find what works well for your taste, your equipment, your room, and last (and definitely least), your budget. I am extremely fussy.
Sounds like you are too :-) so if yours are doing it for you already, why change? You are winning! I rare thing in this game in my books.

Mike, this issue that I experienced was in very low bass, below string orchestra levels typically. So it was synthesizers playing below the five-string electric bass range. I only ran into it on some of my light jazz albums. Also, you if you heard it you might not know it was limited, because there's a strong signal there, but it just doesn't show it's full character. You have to hear it on another speaker and then you'll realize your missing it.

My guess is that well under 10% of my CD/LP collection would expose the issue. So, your odds are pretty good that it will NOT interfere with your enjoyment. The mids and particularly the highs near the top of the heap with the DALIs, IME.