The MiniDamp is a small simple class-D audio amplifier with controls for gain and volume. The internal speaker puts out a surprising amount of volume or you can use the speaker output jack to power an external speaker-cabinet for more volume and clean headroom. Output is approximately 4-watts at 4-ohms. Can be powered with a DC adapter or 9V battery (not included).
9V Battery (not-included) or DC9V Power - Standard Boss Style Center-Pin-Negative power supply only (not-included): Current draw is dependent on the size of the external speaker cab.