Yes, this is kind of a weird question to make, but I haven't found anyone discussing it so I decided to ask it myself. The question: Is it possible to change the pitch of a voice up two tones (for example), in order to create a harmonizer that has no electronics involved? The idea and where it comes from: I am a high school student from Argentina, and went on an exchange for one year to Houston, TX, USA, and now I'm taking all the required exams to get back into my school for this senior year. My music teacher has asked me to come up with an instrument, plan it, build it and classify it. It was going to be a guitar, but I like original creations and came up by accident with a tremolo for voice (easy to make) and thought it would be cool to present some sort of pedalboard for the voice, but with no electronics involved because it needs to be cheap (part of the assignment) and I have no knowledge in electronics (I suck). I just need somebody to tell me that it is by all means impossible (like, don't say I'm crazy), OR somebody to tell me hey, there's that already, somebody came up with it yesterday, and show me a link to it. Thank you beforehand, and if you want to help me with more ideas for hand made voice FX, that'd be awesome! Alejo.