ITEM NAME:Microphone Amplifier Module Reverberation Board XH-M173 Electronic DIY PCB Description: Lin GND Rin: Represents the left channel ground and the right channel in the audio input signal, respectively. Lout GND ROUT: Table indicates the left channel ground right channel in the audio output signal. MIC1 MIC2: used to connect the microphone, the microphone connector can be directly inserted. Music volume knob: used to adjust the background music (accompaniment) sound size. Microphone volume knob: used to adjust the microphone voice sound size. Reverb Depth Knob: Used to adjust the sound level of the microphone sound. Reverb Time knob: Used to adjust the microphone's playback time. Specification: Model: XH-M173 Product Name: Kara OK reverb board Output load: need after class amplifier Chip selection: dual power AC12V Machine size: 100 x 57 x 17mm / 3.93x2.24x0.66inch Package Includes: 1 Piece Digital Microphone Amplifier Module Note: Please allow 1-3mm measuring deviation due to manual measurement. Due to the different monitor and light effect,the actual color of the item might be slightly different from the color showed on the pictures.Thank you! SKU: 0016732273021560.1 Piece Digital Microphone Amplifier Module. MIC1 MIC2: used to connect the microphone, the microphone connector can be directly inserted. Output load: need after class amplifier. Reverb Depth Knob: Used to adjust the sound level of the microphone sound.