Coax AMT's, or not ...
From Piega's site:
"Piega's specialities are the LDR (Linear Drive Ribbon) tweeter ribbons and the coaxial ribbon system. The design of both systems is predominantly based on a strong magnetic field and an extremely thin, partially embossed, foil. For the coaxial system, the acoustic centre of the entire mid- and high-range is at precisely the same point on the X,Y and Z axes. This means that the system is the only real point sound source on the market. Time-aligned emission in all dimensions is the valuable advantage of this uncompromising construction."