An amplification system of the invention can decrease power consumption in a power amplification section if the power amplification section need not be used. The power consumption in the power amplification section can be decreased by shutting off power feed into a voltage amplification stage by a power control section, and the power feed state into a power amplification stage from a power supply section is not changed. Thus, power feed into the voltage amplification stage of the circuit wherein a large current does not flow needs only to be controlled using limiter means also used for a different application, so that the power consumption of the power amplification section can be decreased without the need for enlarging the circuit scale, with saved space, and simply.