1.Multi-function bass guitar amplifier 2.Control :Tone(High,Mid,Bass) 3.Jack : Input, Output 4.Speaker :1*5"*8 oh ... sound quantity. Distorted cut. Distorted gain. The distorted volume, the bass, the tenor, the treble, the reverberation, the earphone outputs, ... sound quantity. Distorted cut. Distorted gain. The distorted volume, the bass, the tenor, the treble, the reverberation, the earphone outputs, ...