OK audio types, here's something you don't see every day...
Attached is the schematic for the Beveridge Electrostatic loudspeaker model 2SW-1. Back in the day it was argued to be one of the finest speakers ever made. Let's figure out how it works.
It has a built-in hybrid amplifier that uses tubes for the output stage. The configuration is novel, allowing for transformerless drive to the transducer panels.
I would love to discuss how the output stage works. Especially how does it bias the driver transistor pair, and how does the output node of the tubes stabilize at a quiescent state halfway between +HV and ground? I am not visualizing it...
Thanks!