Discord Voice Changer for Mac – free

Download and Install CASTER app

Setup CASTER application:

Open CASTER application – installed in your Application folder.

Hit the Add Microphone button and Add your Microphone.

Choose your Monitor device to hear your stream.

Now navigate to the Microphone advanced view mode and add some plugins.

Lets start by adding Apple AUPitch plugin:

The Apple AUPitch can modify your voice.