Classic Music Recreations

I thought I'd share some info on how I recreated George Buzinkai's tracks in the Spelunky Classic soundtrack. I made these in PxTone v0.9.2.5 and heavily relied on Audacity to pick apart the original music and work toward perfecting my recreations. I hope the tips and commentary shared here can be helpful or at the very least interesting!

The big technique I used to dissect the music tracks was phase cancellation. This can be done in Audacity by inverting the sample points of an audio track and lining it up to cancel out another audio track. Because sound is additive, this basically 'subtracting' certain sounds from the original audio track. But they must line up perfectly in order for the phase cancellation to fully take effect.

With this technique, I can easily remove the instrument parts I've recreated perfectly and more clearly hear the parts I have yet to figure out. In this example, I recreated the drums track of Cave and used phase cancellation to hear the original music track without drums. Note: Since the original music tracks are in compressed OGG format, there's still a remnant of the drums I removed due to the artifacts of compression.

Phase cancellation can be used in other ways too! By cancelling out an audio's right channel from it's left channel I can figure out how hard an instrument is panned left or right. If the instrument uses PxTone's time panning feature, I'll misalign the left and right channels a little bit and listen for when they cancel out. This comes in handy for the multi-layered strings in Title and Credits.

I stayed surprisingly organized with my recreation projects which really helped in the long run. I'd save renders of parts I had recreated (example: Cave-DrumsOnly') so I could quickly strip parts from the original tracks using phase cancellation and get to work on the rest.

I also made sure to use the music tracks from earlier versions of the game. In v0.99, the music files were trimmed down to reduce file size, which means an extra layer of OGG compression.

I started recreating Cave first, as all the drums and waves of this track are default instruments that come with PxTone. There's 100 Organya wave samples bundled with PxTone so it was just a matter of searching through and going by ear. Even ones that seemed okay needed to be checked using phase cancellation to be sure I really found the one that was used in the game's music.

Although my Cave recreation was in a good state, I came back to it much later suspecting something was missing. Because of the OGG compression it was hard to tell apart the hihats from the layer of compression noise, but it was indeed missing closed hihats in the first section of the song.

Moving to Title next introduced a new challenge as it featured instrument samples custom-recorded by George Buzinkai. Buzinkai had a few PxTone projects available on their website at one point which had a chance of including the raw samples I needed, but sadly the website is gone now. After months of searching I wasn't hopeful, until finally I found a module archive called Modland safely keeping those original project files from Buzinkai's website.

I'll say it was incredible to get the instrument samples I needed, but it was also amazing to finally hear those compositions I thought would never be found. With this new discovery, I was able to quickly complete the Title recreation.

Prior to getting the strings sample, I recognized that Title had a low bass tone that was hard to hear. I had trial-and-error tested like 30 different Organya samples but none of them worked when checked with phase cancellation. Once I recreated the strings and removed them from the original track, I got a more clear view of the bass wave and identified it as ORG_M36, the one I'd somehow missed...

Lastly, the Credits recreation. Accurately transcribing the fade-out of the instruments at the end took a few days to nail down, but I think I got it right. Here's wher I started using Audacity's spectrogram viewer, which is maybe something I should've gotten acquainted with sooner. This helped me find discrepencies between the original and my recreation, and helped me nail down the volume fade-out at the end. Especially with the sine wave that was hard to tell by ear, the spectrogram made it surprisingly clear if it's volume wasn't right.

I'm very satisfied with how far I've come with these recreations, but one last issue still remains.

The Credits recreation is still using a timpani sample isolated from the original music track itself. Although it doesn't sound too bad, it'd be amazing to find a clean sample of the original timpani! I believe the instrument samples are sourced from a Casio CTK keyboard from the early 2000's so if you have any info, contact me and maybe one day I can update the Credits recreation to V2.

Thank you for reading, and thanks to George Buzinkai for contributing to the great soundtrack of this game! I hope appreciation for their music can stay strong for years to come. Rest in peace.