Registering a Speaker

For a normal speaker variant, use:

DoorBellApi.registerSpeakerVariant(
        id,
        properties
);

Example:

public static final Block OAK_DOOR_BELL_SPEAKER =
        DoorBellApi.registerSpeakerVariant(
                MyMod.id("oak_door_bell_speaker"),
                BlockBehaviour.Properties.ofFullCopy(
                        Blocks.OAK_PLANKS
                )
        );

Again, the properties belong to the addon.