Abstract: The former power amplification circuit usually adopts OCL amplifier,which has stationary working condition,a large dynamic range scope,a good feeling in dynamic condition, good tone quatity and so on .But it has also some defects.When one power amplifier transistor is damaged,it will enlarge the scope of the fault and make the whole circuit not working normally. This article improves the former power amplification circuit .The improved circuit can not only remedy the defect of the former but make it better...