I had an audition at CSA Audio in Montclair, NJ of the Classic Column Mk3. The highs and mids were pristine and very transparent. Female vocals in particular had a noticeable realism. The salesman told me that the engineers at the company worked directly with Dr. Heil in the development of the X-ART tweeter and midrange.
In their upper end products, they use compressed sand to damp vibrations. Build quality is impressive.
I encourage anyone to listen to products from this company. I was impressed...very impressed.