To obtain a sound-adjusting device with a marking function capable of marking a setting state at fine adjustment, or the like, by a simple operator operation, and easily and surely confirming the marking position, and returning to the position.

The sound-adjusting device comprises an operation knob 2 for processing and adjusting the tone, or the like; a rotary encoder (11) for detecting an arbitrary operation position by the operation knob; a storing switch part 12 for marking an arbitrary operation position by the operation knob; a storage part 13 for storing the operation position, when the marking operation is performed by the switch part; and an LED display part 3 for determining and displaying the position, when a manual adjustment means is operated at the operation position stored in the storage part.