recessed mic gain prevents accidental bumps on stage, H1 has a key selector so you can dial-in harmonies that fit lots of songs. Studio quality mic preamp with phantom power, USB connects to VoiceSupport application offering tips, tricks and updates, balanced XLR output, mic control feature allows remote effect on/off via TC-Helicon MP-75 microphone. All Voice Tone pedals can be connected (daisychained) - the first pedal controls the master volume. Includes power supply.