An audio engineering game is on how the active class A device will behave on large signals

One of the games at least.


Should a relative high Rg (grid resistor) be used as on Neumann U47 for example?  If we apply a large dignal to the grid of the VF14 electron tube we will see the biasing of the tube change due to the diode rectification effect.  The signal itself creates a negative (side chain) bias. This changes the transconductance of the tube. And creates an automatic gain control similar to an Altec 436C or RCA BA-6A compressor, limiter.


Should we let the output tube or transformer play serious game (peak limiting overload)?


Reference:


Operating Features of the Audion - Edwin Armstrong


Neumann U47 schematic


Altec 436C schematic


RCA BA-6A schematic


Pleiades V6 schematic