Does the Beyerdynamic M260 handheld ribbon microphone use same back loading principle as M88or AKG D12, D20, D25 etc?

Xaudia has some very interesting photos of the inside:
http://xaudiaelektrik.blogspot.com/2014/06/whats-inside-beyerdynamic-m260.html


It looks very similar to inside the M88. In the M88 were found many multithreaded ropes inside the long tube.


So is M260 using the same principle as AKG D20 of terminating the back of the diaphragm by a transmitiin line having the same characteristic impedance as the diaphragm impedance so that diaphragm sees an infinite length transmission line? (See previous posts on the AKG parent). No standing waves are formed and the frequency response is very smooth.


How about the spiral ribbon Fostex M55RP?