[quote=@EliteCommander]
Honestly, that makes a lot of sense. Sound is vibrations through the air (or any medium, really). Although, lightning can also create thunder so by disturbing the air so...it seems like both would be able to manipulate sound in different ways. 
[/quote]

Electromancy could create thunder as a byproduct, yes, but I think the actual manipulation and use of it in a controlled manner should belong to aeromancy.