To provide a sounder that outputs alarm sound to notify an abnormality in a monitored region. The sounder includes: a sound source that outputs alarm sound when a pulse signal is applied to the sound source; a pulse signal application unit that applies the pulse signal to the sound source; a storage unit that stores plural combinations of a frequency and a pulse width that the pulse signal can take; and a pulse signal control unit that controls the pulse signal application unit so that the pulse signal corresponding to the combination of the frequency and the pulse width stored in the storage unit is applied to the sound source.