Boss aimed to create a stomp box which includes sophisticated sounds that is simple to use and they have done just that.
It creates beautiful, real time, harmonized vocals that follow your singing. When you plug in a guitar, it automatically tracks the chords, a preset key or a combination of both. You can also add reverb/delay and an enhancer with real time pitch correction.
The vocal harmonist is portable and can be run on a 9v battery or with an adaptor.