To adjust sound quality with a simple operation.

When either of preset number buttons 11-16 is depressed, plural frequency band levels of a graphic equalizer are set with preset values of a frequency characteristics for respective buttons. After either of the preset number buttons 11-16 is depressed, whether either of individual frequency bands is selected or an easy operation(EO) mode is selected, while displaying the selection result on a selection display device 20, is selected by using a selection button 8. An adjustment button 9 simultaneously adjusts a level for an individual frequency band where the selection result is displayed on the selection display device 20 or for all of the frequency bands in the EO mode. The adjustment result of the level is displayed on frequency band level display devices 21-27. In the case of selecting the mode by using the preset number buttons 11-16 to adjust the level in the EO mode, the setting value of the selected preset mode is further adjusted in accordance with the preference.