What is a percussive instrument? Something you strike, that hopefully makes a noise, and is pleasant to the ear. Then Percussion must be Combining many different percussive devices and methods that may develop an instrumental derivation of what is commonaly refered to as music. Just remember however that drummers are not musicians, they don't make music, they pound it into submission. Over the last 45 years, i've learned that lesson time and time again. In the first ten years, i thought i was actually making music by pounding on things?
go figure. see Ensembles, and drum lines for more info.