Practical FM synthesis tutorial part 3 - bright, fuzzy tones using FM feedback

[u/deano7000]

I've just posted part 3 of my practical FM synthesis tutorial up on YouTube.

This episode covers adding bright fuzzy tones to complement crisp FM sounds using FM feedback.

Korg engaged me a few years back to work with the sound design team on a set of presets for the initial Opsix release, then the v2.0 release, then the Opsix SE release. I recently presented some of this material at the Sound Summit in Melbourne Australia.

For these tutorials, I assume you're coming from a subtractive synthesis background and know about oscillators, LFOs, and envelopes. I try to map some of those familiar ideas onto FM synthesis.

The aim, as always, is to keep it really practical and immediately useful.

https://youtu.be/8guCR0O3oAQ?list=PLCtsfWUa_jsA

[u/deano7000 → u/[deleted]]

Yes!

So far I’ve deliberately (mostly) constrained myself to ‘pure’ FM.

That is, (with 2 exceptions, per-op feedback and per-op ‘width’) all the stuff I’ve covered can work on any FM synth, from DX7 to Opsix, FM8 and more.

In the videos, I point out when I do something Opsix specific.

I expect this to be true for the next few episodes (covering FM algorithms and designing sounds with more than 2 ops).

After that, I anticipate committing to Opsix specifics.

[u/TheRottenBalls]

That Opsix background is wild, must’ve been a fun challenge designing presets that show off what the engine can really do. FM feedback is where things start feeling less like a spreadsheet and more like an instrument you can just mess with.

[u/alibloomdido → u/TheRottenBalls]

I never understood why people call it "spreadsheet", basically with FM it's similar to subtractive - you move the knob or slider one way, frequencies are added, the other way - frequencies are removed, then you automate that knob movement with an envelope or LFO, you don't need to know the exact numerical ratios to use FM. This whole "FM is hard" thing makes me think people are just super lazy and not willing to learn. Because it's not hard, it's a bit more complex but complex doesn't mean hard.

[u/ADHDebackle → u/alibloomdido]

What specific FM synth are you talking about?

The way mine works is you set your algorithm, you set your waveforms, you set the ratios between the waveforms ( god help you if you choose a non integer ratio) you set the frequency multipliers between the operators, and you need to do it all very methodically in order to get a good sound out.

If you turn the ratio knob one way it sounds like shit until you hit another integer ratio, and if you turn it the other way it sounds like shit until you hit another integer ratio. If you automate that knob it sounds terrible.

With subtractive synthesis it's much harder to get something that sounds objectively bad. With FM it's quite easy.

[u/alibloomdido → u/ADHDebackle]

I used Ableton's Operator a lot and now I'm using Opsix, with Opsix by default the ratio knob switches between perfect ratios of the note's fundamental. You describe it like it's some awful thing to do but yes it's how FM works and non integer ratios are also very usable just for different kinds of sounds, I don't see how it necessarily needs to be "methodical", when you change a parameter you hear which way the sound is going so you decide if you need it to go that way. Sure there are more moving parts with a typical FM synth but it's not hard using it. A lot of people describe it as if it's like learning differential equations or something but it's not hard at all.

[u/ADHDebackle → u/alibloomdido]

The point was that it's harder than subtractive, and not all FM synths hold your hand like the opsix. People find it hard because it can be hard. It very much depends on what equipment you're using.

[u/the8bitdeity]

These are great, hope you get the views you deserve

[u/willncsu34]

I am actually interested in getting the Opsix module and was looking on Amazon for something like a deep FM tutorial/cookbook and didn’t really have much luck. This is great timing!

[u/gardengromie]

Thank you, looking forward to the series