The amplifier features specialized processing for karaoke vocal enhancement: Vocal Effects : Includes four digital effects— Reverb, Echo, Repeat, and Delay —to produce a natural and professional vocal sound. Key Control : Allows for pitch adjustment in 11 steps ( plus or minus 5 to match the singer's vocal range. Independent Equalization Microphone EQ : 3-band adjustment. : 2-band adjustment. Visual Indicators