Konami's VRC6 Memory Management Controller chip was the stuff of magic. When integrated to a Famicom cartridge, the advanced MMC chip added three extra sound channels. That's why Castelvania III's Japanese soundtrack is indisputably richer than its Western counterpart.
Wanting to give the classic Mega Man 3 soundtrack a bit of a boost, Atlanta-based chiptune artist RushJet1 spent nine months giving the soundtrack a VRC6 makeover. Destructoid's Tony Ponce has the lowdown:
"Over the course of nine months, Atlanta-based chiptune artist RushJet1 used the power of the VRC6 to completely remake Yasuaki "Bun Bun" Fujita's Mega Man 3 soundtrack. The original MM3 OST is nothing short of amazing in its original form, but RushJet1 takes it to the next level with tons of creative flourishes and interpretations. For example, this is Magnet Man's NES theme, while this is the VRC6 update."In the video above, RushJet1 plays through Mega Man 3 with his new audio layed on top. Amazing stuff. I mean seriously; listen to how awesome Proto Man's theme is on VRC6. Grand! Be sure to hit up the link below for details on how to download the entire soundtrack!
Credit: Destructoid [Mega Man 3 OST gets a VRC6 chiptune overhaul]