Digital reverb effects, speakers, functions, and microphones form the KTV sound system and are an integral part of the system. When the speaker characteristics are fixed, a good pre-stage digital reverberator can improve the effect of the entire system, thereby bringing a relaxed and pleasant singing feeling to the singer. DSP99 is specially designed for professional karaoke, through precise simulation The circuit signal audio device can bring out a variety of excellent singing effects and mixing functions. There are a total of 99 digital reverb effects to choose from. Independent volume adjustment for Bluetooth, music, reverb and microphone makes singing more professional, relaxed and free