Resident Evil 3 Nemesis Clock Tower Music Box Guide

It's All about using your ears really but here: Dn. - Dn. - Dn. - Up - Dn. - Up
The other Code - Dn. - Dn. - Dn. - Dn. - Up - Up
Or This One: Up - Dn. - Dn. - Up - Up - Up
Or it seems to be other code to this.