Found this little experiment on my Mac tonight. I had forgotten I did it.[audio https://dl.dropboxusercontent.com/u/18276384/vary_seq.mp3]
It isn’t really a piece of music — just a texture. I suppose it’s post-minimalist, if you like genre terminology: It’s not intended to go anywhere, but it is intended not to be boring or dull while hovering in one spot.
Inspired by hardware step sequencers, which have a limited number of steps but leave open the possibility of modulating the tone while the sequence plays, I thought I’d try to write a simple step sequencer in Csound and give it an interesting amount of variable playback. The pitch sequence table is 16 steps long, but quite often the sequencer resets to the start of the pitch table before all of the steps have been used. The pitches are defined as ratios in just intonation, and after being read they’re multiplied by some factor (usually 1.0, but sometimes 1.5 or 0.75). The table of rhythm values is separate from the table of pitches, and is a different length, so you’ll hear the same rhythm over and over, but in different parts of the pitch sequence. Variable modulation is being applied to the panning (obviously), the portamento rate, and the filter cutoff and resonance. The final few lines of code add a stereo delay.