These basic bass controls were obtained from an article in Electronics Now magazine in February 1995. They are basic passive circuits in (a) basic tone, (b) boost, (c) cut, and (d) flat response.
We found this circuit in a 1964 Electronic Design. The components are from that time, but the...
This two-transistor circuit was found in a 1969 US documentation. Modern equivalent transistors can...
I found this simple circuit in an English magazine from 1984. The circuit can be assembled easily...