There is one last thing we need to do.
These drums, while powerful, are practically useless here in town.
If you want to get the most benefit from them, you'll need to spread them out. I'd suggest one for each territory here and in Zandalar, to help you when you are on a quest and to keep you at your strongest when you're behind enemy lines.
Look for someplace centralized in each territory to place drums.
Once you return, I'll show you how to make the mallet needed to utilize the drums.