9 Process - Tuning Parameters
This is actually a key concept, so DON’T SKIP THIS BIT. It’s the difference between a random collection of sounds that wobble about randomly, change notes randomly with very little coherence or musicality, or something that’s actually listenable and identifiable as music.
Key idea
As with the advice to balance unexpected and predictable, the advice here is to listen to the results of the generative processes and apply your musical ear whether you feel it passes the test of being pleasant to listen to for extended periods without any particular sound, pitch, volume or other modulated parameter catching your ear.
9.1 The Problem
We defined “generative” music in our first chapter. There we defined it as “music (that) should be able to go on indefinitely, with enough going on to make it interesting, but without anything particularly”sticking out” to catch the listener’s ear”. When we use random processes to generate notes, modulate parameters, change the timbre and qualities of sounds, there’s a danger that this randomness will produce sounds that do “catch the listener’s ear”, or more than that grate the listener’s ear.
9.2 The Taste Test
How to avoid this? Well, as chefs prepare dishes they continually taste and adjust seasoning so that the end result is neither overly-seasoned nor under-seasoned. Basically they taste and add salt throughout the process. Similarly here, I suggest that you listen at each stage and adjust the amount of randomness, the amount that modulation sources are changing parameters, and whether there’s too much unexpected stuff going on, or whether the track is too static and doesn’t change enough. While listening I find it best to try step away from the Ableton Live session, or minimise the Live screen so that you can concentrate on listening and not on what’s happening within the Live set. Some producers listen to their mixes from another room, or with the volume level low, to see if anything “pops out” in the mix. I like listening to my generative music while walking the dog. I make a mental note of anything that catches my ear - but you can also note things down physically in a book or note for later.
9.3 Waving, not droning
In the same way that waves on the ocean sometimes peak together to form very large waves, it’s possible for random processes to suddenly produce things that don’t sound right. And like the waves on the ocean it’s sometimes difficult to tell when this is going to happen. For example, your modulation of volume and sound timbre may cause a period where overall volume of the mix becomes low and dark, essentially causing the whole track to go through a “quiet patch”. If it does this, then consider changing the range that the modulation applies - making the modulation more subtle - or changing the period of the random process. If your LFOs are sine or triangle waves that have even number period (maximum effect every 2, 4 or 8 bars) then eventually all of these will reach their peak (or trough) together - after 8 bars - and this will keep happening every 8 bars. Instead if the LFO period is a (large enough) prime number then the peak or trough will take much longer to happen and may never repeat exactly the same. Small amounts of modulations and uneven (and to be honest longer) modulation periods will keep the movement happening in the music without it becoming predictable. You can always use a modulation source to change the period or amount of another modulation source.
9.4 Be random, but not too random
Constraining randomness can be done up front in modulation - you can change the upper and lower limits of the modulation - and you can apply constraints to MIDI notes via Scale quantisation, you can have sequences that evolve randomly and so over time transform themselves but in a way that isn’t jarring. All of these are ways to keep the randomness in check. As with the Taste Test (described above) you should check in with what you’re producing at each step to try to keep unexpected and predictable in balance. This should keep your tracks from being too much of one thing or the other.
9.5 Tune the parameters
The amalgamation of all of these steps is to “tune” the random and other process to find that sweet spot where things work together to produce something that you and a future listener might enjoy listening too. As mentioned above, try to do this throughout the process rather than just at the end. That way you can balance as you go and achieve something that sounds good in its entirety rather than a combination or collage of different ideas.