Switch to "Animate" view.
Select one of your animations.
Select the magic wand icon "Animate Effects"
Click on the + icon near "Sound" effect type to create a new particle keyframe.
Edit the values on the "Keyframe" panel.
- Name: name of the sound, use the ingame Minecraft particle name. You can also use custom sounds from your resourcepack.
- Volume: the volume of the sound.
- Pitch: the pitch of the sound.\
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