Guitar Pedal X - GPX Blog - Electro-Harmonix's Intelligent Harmony Machine delivers a Neater and Smarter Harmonizer with Classic Pitchfork style Pitch- Shifting onboard too
Top 9 Pitch-Shifting & Harmonizer Pedals For Guitar & Bass – My New Microphone
Electro-Harmonix Pitchfork Pitch Shifter Effects Pedal | The Music Zoo