Rockman World 2/Mega Man II Music Improvement

Download IPS patch

Download GBS soundtrack

Watch me play this hack semi-competently

Rockman World 2/Mega Man II is notorious as the black sheep of the Game Boy Mega Man games for many reasons. Perhaps the most glaring of these is its peculiar soundtrack, which is bizarrely high-pitched, off-key, and extremely grating compared to pretty much any other Game Boy game, let alone the rest of the series.

This hack attempts to improve the music by fixing two apparent errors:

1. The first is an objective programming mistake: the game's note-to-frequency conversion table is wrong. Some values are correct while others are one higher than they should be, resulting in over a quarter of the notes playing off-key.

2. The more obvious problem, and the more subjective one, is that much of the music has lead instruments set an octave higher than most people find pleasant. Strictly speaking, I can't prove this is an "error", but I find it almost impossible to believe that the music as played in the game is how it was really meant to sound.

Problem 1 is a simple fix: the frequency table has been regenerated with the correct values, fixing the out-of-tune notes.

Problem 2 has been handled, in most cases, by lowering the two square channels (used for leads) one octave and leaving the wavetable channel (used for bass) untouched. A few tracks have been handled specially:

  • Stage select and stage intro themes:
    Wavetable channel used as a lead and lowered an octave.
  • Wood Man's theme:
    Untouched, since it's actually at a sane pitch to begin with and lowering it just turns it into a dissonant mess. (Also, why does this track quote Top Man's theme from the NES version??)
  • Hard Man's theme:
    Channels 2 and 3 are used as dual leads at a reasonable pitch, so they both stay the same. Channel 1 is bass and gets lowered. Might benefit from having channel 1 stay at the original pitch for the final bit before the loop, but if I let myself get that fine-grained, I'll be rewriting the entire soundtrack before I know it.
  • Boss theme:
    Squares stay the same. Wavetable is lowered so the track actually has some bass.

To my ears, this results in a much-improved listening experience. Turns out once the problems are fixed, some of the music in this game is actually surprisingly pleasant! It might not fix the decidedly aberrant gameplay, but personally I found the game much more tolerable like this.

Note that the sound effects are unchanged, as they're stored in a different format that directly specifies the intended frequencies instead of doing a note-to-frequency conversion.

I'm very curious as to how the music ended up the way it did, because pretty much anyone could tell you it sounds terrible. My best guess is that the sound programmer couldn't figure out how to fix the problem with the frequency table in time for release, so they tried to make it less obvious by shifting everything up an octave. Who knows, though? Whatever the case, I think it's safe to conclude that having an outsourced developer make a game in less than five months for a series they've never worked on is probably not the best idea.