That’s it !
The best explanation ever !
One thing to mention in favour of the crystal earpiece, it has such an incredible high impedance that it has been and still is used for crystal radios.
It poses no load on the circuit and is very sensitive for very weak signals.
In our Lectron environment, we can perform many cool experiments with the 300 Ohm earpieces, not yet mentioned in the manual.
But that’s a different topic, I will come back to this later.
Greetings