Jim, search for DALI here on A'gon and you'll find plenty of discussion, mostly by me, about that very topic.
I was disappointed in the low bass of the Helicon 400MkII that was very favorably reviewed by Michael Fremer in Stereophile. It also measured well, yet I heard it take on a one-note character below around 40hz.
I tried several amps and none fix it; however, I found that it preferred a lot of power.
Rethinking the issue I went back to the scene of the crime this week. The room where I was listening did have some bass corner treatments. I'll try to get by again next week with my test CDs to see if moving the bass traps out of the room doesn't fix things. (Strangely it doesn't seem to impact any of the other speakers in the room.)
I spoke with someone that almost went to work with DALI as a US representative. He says that they purposely use relative thin cabinet sides and that may make them more room sensitive than many other speakers. That's just a theory, but I WILL go back a third or fourth time to see if this issue can be be fixed or at explained.
Dave
