We found this circuit in a 90's EDN. The circuit is based on a control integrated that is still common in these types of applications. The circuit uses a PROM.
Circuits like this one, using the LM386 audio amplifier, are available from other sources in this...
This bass and treble control only attenuates the corresponding signals, requiring further...
Using a large inductance, this circuit was found in a Popular Electronics from the 90s. The...