The harmonizer pedal (sometimes called a pitch shifter) is a very popular guitar effects pedal, particularly with lead guitar players or anyone who is looking for a unique effect for soloing. A harmonizer pedal works by processing the incoming guitar signal, identifying the note, and creating harmony notes above or below the notes you are playing. You can specify what scale and intervals you want it to play. It's worth noting that some people also now refer to "vocal harmony" pedals as harmonizers, so be aware of that potential confusion. So if you are looking for a cool new effect to add to your arsenal, we hope you will check out the reviews on these pedals and find the best harmonizer pedal for you.