10.9.10

The Tao of FM Synthesis #4 ~ Ockham's Razor


“Entities should not be multiplied without necessity.” (William of Ockham)

“Nature operates in the shortest way possible.” (Aristotle)

“Everything should be made as simple as possible, but not simpler.” (Albert Einstein)
Everybody who’s a beginner at sound design knows this situation: you’re tweaking and you’re tweaking but the sound isn’t changing. So you search and find the problem, or you give up.

And everybody who’s a bit more experienced knows a similar kind of situation: you’ve created a great sound but you want to refine it just a little bit more. Suddenly you notice you’ve gone too far. You’ve made a mess of it and now you want to return on your steps but you can’t. You’re tweaking and you’re tweaking but that almost perfect sound isn’t coming back.


There’s a general kind of design principle known as Ockham’s Razor. It says that given a choice between two equivalent designs, the simplest one should be selected. Ockham’s razor can be applied to sound design as well. It would go like this: every sound parameter you edit or change or use has to be clearly audible and relevant to the result you’re aiming for. Otherwise you’re wasting your time.

Every time you touch a button or a slider you should hear a certain effect, preferably a somewhat predictable effect. If you don’t hear what you expected to hear you either need to learn more about sound design basics, or you need to simplify your current approach to the design of your sound (maybe mute an oscillator or switch off an envelope). In short, you should know and hear what you’re doing, or else simplify. You should also know when to stop :-)

What is the reason why everybody liked the original Google search engine? Simplicity and ease of use, and smart programming behind the scenes. Unfortunately, most apps on your computer, whether for music or graphics or whatever, work in exactly the opposite way: too many features, compatibility issues, bullsh%t updates and bugs.


Making music on a computer can be great but it can also be a pain in the ass. Look at the design of a flute, a violin or even a cymbal: simple, efficient and it looks good too. It might take years to learn how to play a violin or a flute, but at least you don’t have to worry about bugs and updates.

When you’re making music on a computer it’s a good thing to remember Ockham’s Razor, especially while trying out new software. If you don’t understand how a certain synthesizer works you shouldn’t blame yourself, but the ignorant people who designed it. Always keep in mind that it’s perfectly possible to make great electronic music with the simplest tools and methods. Certain software developers may claim the opposite, but that’s just because they want to sell you MORE of the same crap you never really needed in the first place.


For beginners, understanding FM Synthesis is hard enough without the unnecessary options, the 50 different envelopes, 50 new algorithms, 8 oscillators per voice, 128 part multi-timbral, multi-delay, fat chorus, analog distortion, valve-like warmth bla bla.

In this series we have started from scratch, keeping in mind what’s unique about FM:

It’s a relatively EASY way to create ORGANIC, COMPLEX (as in musically interesting) timbres.

Now, before we continue with the practical FM tips and the sound examples, it should be clear that the focus will be on:

- creating original sounds (not: how to imitate a fender rhodes piano)
- creating basic timbres and FM sound effects (not: explaining how a certain FM synth works)
- improving your ‘vertical listening’ skills through fine-tuning timbres and ratios (not: explaining how a 50 stage envelope generator can do flips and twists and loops in ‘evolving patches’)

And to ensure we keep it simple the basic setup will be like this:

- a maximum of 4 oscillators (or operators or ‘hands’ and ‘throats’)
- only FM-synths that have a ‘ratio’ control will be used in the sound examples
- no use of effects like delay or chorus

While it’s not really possible to give a systematic overview of all possible FM timbres you can have certain categories, for example certain types of ratio values. Below are a few examples of ratio categories, using only 2 sounds to create the FM-effect. Try to hear what is special about each of these 3 categories.



1. Basic sound : Effect sound ratios where the ‘Effect sound’ is a ‘whole’ number

2. Basic sound : Effect sound ratios where the ‘Basic sound’ is smaller than 1

3. Basic sound : Effect sound ratios where the ‘Effect sound’ is smaller than 1

OK, that’s enough for now. If you want more there's a related topic that should keep you busy for a while, but only if you're into mathematics: below is an example of a ‘family of ratios’ which all sound the same.

2:5, 3:5, 7:5, 8:5, 12:5, 13:5, 17:5, 18:5

Check this if you want to know the theory behind it.

Next time we’ll add envelopes to make the basic sounds a bit more interesting.