It was most commonly used on guitars, and many of the most iconic guitar gods of the 80’s had one in their rack at some point. This made things a little easier, but not perfect. Then, in 1975 the Eventide company introduced the world’s first digital pitch-shifter – The Harmonizer. Double tracking was a common technique going all the way back to the recordings of the Beatles, but was really only useful at hiding inconsistencies in vocals. Modulation effects like chorus or flange could help, but imparted a specific sound that might not fit the song. You could slow down or speed up the tape that the track was on, but that introduced a lot of headaches. There were few studio tricks you could use to cover up a shaky performance. In the golden days of analog, pitch correction was a fairly tall task to achieve. Let’s dive in to how they work and see which one is right for you. While they have many similarities, they also have some critical differences.