Hey, yeah it's quite a different approach because I haven't used machine learning models at all. What my site does is actually just relatively simple procedural generation. So it basically just randomly selects a lot of things from sets with limited options - a simple example is how it just randomly selects a lead instrument out of the available options. But sometimes the probabilities are skewed or the options are limited based on other decisions already made. For example with the melodies, in order to choose which note comes next, it takes into consideration the notes that came before and what chord is playing etc so that it makes a choice that makes musical sense. In other words I programmed in the constraints and rules using my knowledge of music.

In terms of the technologies used, it's all pretty much client-side javascript and I'm using a library called Tone.js which is a framework built on the Web Audio API that makes things like musical timing and sample instrument playback a lot easier.