The operational amplifier for this tone control found in a 1977 Signetics manual may be the 741. The power supply must be symmetrical and the signal cables short. The bass gain is 20 dB.
Found in a 90s Popular Electronics this circuit has its gain given by R2. This component can be...
This circuit was obtained in an English publication of the 80's, finding applications in...
This circuit was found in a 1977 Radio Shack documentation. The circuit is TTL, which must be...