Keep level up effects and sound separate

[madtomic]

How do I set the sound and not use the effect or set effect but no sound. It had been awhile since I play with this. Can you please remind me how to use entity.player.levelup for sound?

# level up effects
effect:
    lightning: false
    # List of all available particle effects
    # https://hub.spigotmc.org/stash/projects/SPIGOT/repos/spigot/browse/Bukkit-Patches/0006-Add-Particle-API.patch
    effect: ''
    sound:
        # set this empty in order to disable it
        type: ''
        pitch: 0.1
        volume: 10