To obtain a speaker system using passive radiators of simple structure for suppressing edge radiation sound distortion and reducing generation of distortion by second harmonic.

A speaker unit in which an acoustic signal is input and the passive radiators are attached on the front surface of a cabinet of passive radiator system, a plurality of passive radiators including the ones using diaphragms in the same shape, with the same size and making the installation directions of roll edges opposite are used, the respective ones are adjacently arranged.