The Pitch correction does'nt need any input but in order for it to produce the right harmonies 3rd and 5th above and below it needs the appropriate Guitar chords for a reference.I havent tried it with my bass as a Input I just grab a line out of the Guitarist Digitech if Im going to use the harmony portion.
It was explained to me that the pitch correction works like a basic tuner where if you are sharp or flat it will correct you within that note but if you are trying to sing a "G" and you are really singing "A" then it will pitch correct the "A" Hence its called pitch correction,I could use a note correction at times thats for sure.
