Gobel and the Bending Wave


An article at Stereophile regarding the Gobel Divin Noblesse speaker caught my eye recently:

https://www.stereophile.com/content/g%C3%B6bel-loudspeakers-cables-engstr%C3%B6m-pre-and-power-wadax...


Jason Victor Serinus made a simple mistake and listed the AMT tweeter as a "bending wave" transducer. He's corrected the error, but the "fix" was just as curious. According to the Gobel website, and JVS's correction, the midrange drivers, which for all the world look like FaitalPro 8" mids to me are "bending wave" transducers in this model.


http://www.goebel-highend.de/products/divin-noblesse.html


These midranges look nothing like the bending wave planar transducers used in the Epoque line, or described by their technology page here:

http://www.goebel-highend.de/technology.html

So, without being able to order and disassemble these $190K speakers, I'm really skeptical that this description of the midrange drivers is accurate.


That is all,

Erik
erik_squires
It would seem apparent that for wave  bending the cone cannot be a "rigid" piston.  
it woukd seem apparent that the cone cannot be a "rigid" piston.

In that case, we do not describe it as pistonic. :)

The term comes from the theoretical ideal of having a piston with a flat, infinitely rigid surface, exactly like a piston, operating in a cylinder.
That’s fine theoretically but in practice the bottom ported Ohm Walsh driver produces sound both pistonically and via wave bending at the same time.  
That’s fine theoretically but in practice the bottom ported Ohm Walsh driver produces sound both pistonically and via wave bending at the same time
.  

But not at the same frequencies. That's what I mean by simultaneously. It is a bending wave transducer to a point, below which it becomes pistonic.