Alright listen up I'm gonna tell you how to do the drum stuff without using a hex editor, because fuck, I don't know this shit, so I better just experiment and find a way how to do things, and wow, something popped up in my head and I was like 'Oh yeah pixel made pxtone which has pxnoise which...
Wow, just wow.
No wonder why this game took 5 years to make.
And also, go here.
Then download the Org Maker 2 English Translation, open it, then load the lastbt3.org file from your Cave Story folder and mute the the non-percussion sounds.
As shown here:
Enjoy!