[Aerodyne]

It may be that I've missed something here... or age has finally and perhaps irrevocably caught up with me... but I am rather puzzled by this circuit which shows the two halves of a double triode with the anode of one directly connected to the grid of the other, with the audio output taken from the cathode of the latter triode. My question is this: what is the point of this circuit? It isn't a cathode follower, at least not in the accepted sense (as far as I can see) and if it is a means by which impedance is modified, how does it work?

Can anyone provide a clear and straightforward explanation? Yes, I have searched books and the net and can find nothing about it.

Tony