The pro amplifier has a built-in efficient transformer and high capacity filter power supply. This helps ensure lower distortion, greater low frequency control force and clearer voice when the amplifier outputs at full load. The pro amplifier offers three output modes, including stereo, mono and bridge output. The use of time delay relay circuit allows soft start, which helps protect the speaker against electric shock during POWER ON or OFF. The pro amplifier is widely used on many occasions for speech transmission and sound reinforcement. It owns three output modes: stereo, mono, and bridge.And it has high sensitivity safety protection circuit as well as high efficiency dual fan cooling channel.