If you don't have a touchpad, a horizontal scrolling can be done via shift+mouse wheel (generally on the web). Also, I have a second color scheme that I tried to optimized for people with color vision deficiencies.

My big dream now is to have all piano rolls in DAWs support 12-coloring (in any color scheme really), so that the music can be seen as less complex, less gatekeeped and less entangled. It's not as hard as I've seen it before.

Source code: https://github.com/vpavlenko/rawl

It currently doesn't play music from Russia or Türkiye (=requires a VPN), because I rely on corsproxy.io internally which blocks access from those countries. I plan to rehost stuff on S3 soon to fix that.

Also, it's more performant in Chrome than in Safari - audio clicks less.

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Backstory: I quit Whatsapp in 2021 to focus full-time on studying music theory. Along that I've assembled a list of resources to see the frontier: https://github.com/vpavlenko/study-music

My biggest inspiration is Hooktheory - an interactive book that teaches how melody and chords interact in Western pop music. After it I wanted to study how the rest of the arrangement works - what the bass line is doing, how is melody doubled, what chromatic chords are possible, are there any functional pre-dominants and dominants in mixolydian or dorian etc.

I wanted to focus on music for which the complete arrangement is clean and available. This is early chiptune (NES/Genesis) OSTs and MIDI arrangements (primarily created in 1990s). As I plugged MIDIs into my front-end, I discovered that the harmonic analysis - the cornerstone of studying Western harmony - can be done by eyes in real-time. That is, if you color the notes consistently, the chords start to stare at you, sharply and memorably.

I'm intrigued by latest shifts towards corpus studies in music theory and I'm generally happy that nowadays the research is not just about classical music anymore. At least in the West.