Provided are a magnetic transducer and a thin film magnetic head having good thermal stability and capable of obtaining a high exchange coupling magnetic field, a method of manufacturing a magnetic transducer and a method of a manufacturing a thin film magnetic head. Downstream processing circuitry is coupled to the high-pass filter, and upstream processing circuitry is selectively coupled to the first low-pass filter and the second low-pass filter in response to an indicium of a desired spectral region. When the piston is located in the proximity of a bottom dead center, an outermost portion of the counterweight crosses an imaginary extension line extended from a piston pin in an axial direction of the piston pin.