We found this active crossover in a Radio Electronics magazine from June 1961. Note the different adjustment ranges. The signal must be applied to the amplifier input.
In the figure we have a high stability voltage reference, providing a voltage of 10 V at the...
We find this circuit in an American 1980s documentation. Integrated circuits are uncommon today as...
The diagram is from a 1990s document. The integrated circuit must be equipped with a heat sink. The...