BOSS VT-1 Voice Transformer Vocal Effector w/ AC 100V Adapter & Box Repaired

With these functions, the VT-1 enables creative audio processing for vocal performances and audio production. Its main features include the ability to shift the pitch up to ±1 octave and adjust the formants independently, allowing you to change the timbre of your voice to sound like a different gender or create a robotic voice.

eBay