Change the pitch and speed of your voice recordings or any song in your music library. Make your voice sound like a man, zombie or monster. There is also a function to make your voice or music sound slurred by playing it slowly. Your Music library: Pick any song in your music library and make it sound like a man is singing it. For example, hear what it sounds like when a man sings a Katy Perry song. Voice Recordings: Deepen your voice recordings with Manify. You can also slow down the playback of your recordings giving you the slurred voice effect.