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.
This adjustable circuit from 0 to 200 nA was found in a 90's EDN. The components can still be...
We found this circuit in 2005 Linear Technology documentation. MPOSFET is load-matched. The...
This circuit generates audio tones in a speaker with controlled frequency and volume. The...