J loved banging on things from a young age.
This picture was actually taken the first time he decided to sit up on his own - when we put a pot in front of him and gave him a wooden spoon. He was a very content baby. The next few weeks - well, ok, the next year and a half - were spent trying out different sound wave formations by banging on anything we'd let him.
Things to try:
* Different objects doing the banging: sticks of various sizes, lengths and diameters, wooden spoons vs. metal spoons, water bottles full of water vs. rice.
* Banging on different objects: floor, walls, pots and pans of various sizes, some unbreakable toys that could get beaten up a little bit, play or real drums.
* Beat fast!! Beat slow. Can you repeat a rhythm? Put on music and tap out some beats.
Remember to set boundaries. Don't let your kid bang on or with anything valuable or breakable.
I'm going to recommend this experiment for the babies, just for sanity purposes. Toddlers + banging = bigger headache!