The Melodizer is a variation on the Beat Generator. It will constantly generate a tune with a “melody” and a “bass line” by looking at the settings every measure and generating a measure with those settings. Each big slider represents a 16th note in a one bar loop. The value of each slider is the probability that the program will choose to generate a note on that 16th note when it generates a measure. The actual pitch it chooses for the note is determined by the current key and scale, as well as what the previously generated pitch was. If you look in the Scales.pde file you’ll see that for each pitch in a scale, I’ve encoded which steps in the scale are legal next notes. It’s a pretty crude melody building algorithm, but it does give the output a little bit more musicality. The drum beat is always the same, but there are three toggles that let you turn off the parts of the drum loop you don’t want to hear.
Some other things you can adjust are: tempo, shuffle (how much it “swings”), the waveforms used for the melody and bass lines, the volume of the melody and bass lines, and of course there is a button for randomizing the note probabilities.