Fathom Synth Development Thread

[Sinthoid]

Funny how you say that as if FM synthesis using resynthesized samples as operators wouldn't be the greatest thing to ever happen.

[Distorted Horizon]

Funny how you say that as if FM synthesis using resynthesized samples as operators wouldn't be the greatest thing to ever happen.

Ever tried Diversion?

[Sinthoid]

I'm familiar with diversion, but in Fathom it would be a completely different ballgame with it being fully modular.

[fmr]

Funny how you say that as if FM synthesis using resynthesized samples as operators wouldn't be the greatest thing to ever happen.

I have messed with FM mixed with samples (still have a TG77 and a SY99). It's difficult to control and you have to be very careful and criterious with the chosen material to achive some interesting results. Usually, a single sample modulated by a sine is enough. And you can achieve that easily in Fathom, when you will have samples available.

Besides, I don't know what's the problem with FM, really. I just tried, and chieved some FM timbres quickly. I just used two and then three basic oscillators (once carrier and two modulators), but I could copy more and achieve any algorithm routing I want.

Start by just creating what will be an operator (adding a single oscillator and placing all the modulations). Then just copy that until you have six operators. Then create the routing you want (that's your algorithm).

[zakufan]

my software update pass code does not work for the latest update. I am updating from v1.11. Do I have to purchase update again?

[mutantdog]

my software update pass code does not work for the latest update. I am updating from v1.11. Do I have to purchase update again?

They changed codes since then. You need to email dev for the new code.

[Tj Shredder]

Start by just creating what will be an operator (adding a single oscillator and placing all the modulations). Then just copy that until you have six operators. Then create the routing you want (that's your algorithm).

The routing I want has feedback! Not possible yet as far as I know...

[Scrubbing Monkeys]

[/quote]


Besides, I don't know what's the problem with FM, really. I just tried, and chieved some FM timbres quickly. I just used two and then three basic oscillators (once carrier and two modulators), but I could copy more and achieve any algorithm routing I want.


[/quote]


I have tried and tried and tried. But.........I have always used The FM section in each Oscillator. and with that ....when I change the first to carrier or modulator the second follows and there is no change. Perhaps I am thinking to deep. Maybe I should used just the basic oscillators as you say and connect them together without going to the FM page. Is that what you are doing?

[zzz00m]

Regarding FM. I'm a total noob. I got my first synth in the 80's, but it was a PD, phase distortion type of synth. Thankfully it avoided an FM operator algo style of synthesis with carriers and modulators. Instead. it emulated a subtractive style synth with basic digital oscillator waveforms, ADSR envelopes, etc., so it was my intro to basic synth programming. Happy times!

Never bothered with the DX-7 or any of the virtual FM clones. That is, until I recently got curious about Dexed and the bazillion free DX-7 patches available.

Anyway I recently followed along with a DX-7 programming video to make three sounds on Dexed from scratch, a bass, a bell, and an electric piano. I think I came close on the first try.

This tutorial >

So then I tried setting up a basic two operator FM sound in Fathom and got completely lost. I was able to connect two basic waveforms as suggested in the Fathom user guide chapter 5, resulting in a sine tone. I was able to get something approaching a triangle wave, but not quite. Got plenty of other weird sounds. So I am at a loss as to how you would shape things, or modulate them, in Fathom FM to get the different waveforms.

Open to suggestions, as I am sure it is my fault for missing something obvious. But I am looking at it as a challenge now, just because it is there.

[fmr]

Open to suggestions, as I am sure it is my fault for missing something obvious. But I am looking at it as a challenge now, just because it is there.

I just connected three basic oscillators with sine waves, and created modulators (envelopes) for the volume, and for the Ratio Multiply and Amount (one envelope for each oscillator). I wasn't trying to come up with anything else then some FM'ish tones, and I quickly got that.

I even don't know if what we get in Fathom is true Frequency Modulation (which is harder to control) or Phase Modulation as in the DX7 (which is more controllable). I still have to check if the manual clarifies that.

Again, when I want FM, I turn to a more specific synth, like DX7 V or FM8, which have a programming environment I'm more familiar with. But now that this is being discussed, maybe I will take a couple of hours to try to come over with something resembling more a true FM synth

[FathomSynth]

There's one tricky part to Fathom's FM (which I still have not made time to correct).

Modulations to any of the FM parameters such as Ratio Multiply, Ratio Divide, Amount, need to target the dials on the first oscillator not the second, otherwise they will be ignored.

The FM dials on the first and second oscillator are synced so if you change one it will change the same dial on the other oscillator, but I never had a chance yet to do this for the modulation of these dials.

So you just have to remember to modulate the first oscillator.

Conversely, parameters which impact the final output such as all the detune parameters, volume, pan, etc. need to be done on the second or last oscillator since the last oscillator precedes the output.

If you remember these two rules then you should fine.

FM is notoriously hard to control on any synth since multiplying two waveforms can very quickly create very high complexity and complete garbage in the output. But the best rule of thumb for FM is to start out simple with two oscillators both set to sin waves and only increase the complexity of the parameters gradually after you understand exactly what you are listening to.

Also, be very careful about the FM Ratio Multiply dial, if this dial is not set to multiples of 0.5 it tends to create complete garbage. One trick I've used for some of the FM presets is to carefully modulate this dial with a sequencer envelope with only flat edges, making sure that all the levels in the envelope correspond exactly to multiples of 0.5 on the Ratio Multiply dial.

Here are two example presets showing some effective use of Fathom's FM.

The first is an FM stab which modulates the FM amount with an ADSR and the second is a rhythmic modulation of two FM parameters.

Fathom FM Presets.zip

It might be worth trying to talk Scrubbing Monkeys into making a short FM tutorial video. Some of his other videos have simplified some of Fathom's more complex hurdles.

[fmr]

There's one tricky part to Fathom's FM (which I still have not made time to correct).

Modulations to any of the FM parameters such as Ratio Multiply, Ratio Divide, Amount, need to target the dials on the first oscillator not the second, otherwise, they will be ignored.

So, we can't chain more than two oscillators (like having, for example, oscillator 3 modulating oscillator 2 and oscillators 2 modulating oscillator 1)? This would be necessary for recreating some of the DX7 algorithms.

I thought that those controllers would be independent on each oscillator. The same with the detuning.

Anyway, as I said, there are easier instruments to get FM sounds.

[zzz00m]

Thanks for those FM presets. That "FM Stab" sounds very FM'ish! I'll have a play around with that one. It's good to have a working example as a starting point!

I can see now that earlier I was missing the use of envelopes to modulate things with, and was just attempting to use the FM controls in the oscillators.

[FathomSynth]

You can connect as many oscillators in FM as you want, either in series or even in parallel, and Fathom will mathematically figure out the correct FM output signal based on summing all the FM frequencies correctly according to the signal flow.

However, I would not recommend just throwing in oscillators and connecting them in FM and expecting anything tonal to result. It is best to start with two oscillators in series, then move to three oscillators in series only after you understand exactly what is going on. Otherwise you are going to end up with garbage.

There are three presets in the Retro folder which use three FM oscillators in series with some cool results:

FM Bass Three Stage Mono
FM Bass Three Stage Slap
FM Bass Three Stage Twang

My regression tests cover two or three FM oscillators plugged into a single oscillator which in turn is plugged into another oscillator, and other such complex combinations, and it will run. But I've never managed to get anything tonal out of such nodes.

If your goal is to fake out Fathom or make it look like an DX7 flow chart then you are going to end up with a mess. My advice is to do it in stages and understand exactly what is being multiplied by what. Then you will end up with some cool sounds.

[fmr]

Oh, I know how to move among that mess, don't worry. I was only questioning if, when I have a series of three oscillators, your statement will maintain: "Modulations to any of the FM parameters such as Ratio Multiply, Ratio Divide, Amount, need to target the dials on the first oscillator not the second, otherwise, they will be ignored."

And in that case, the second oscillator (which is also a modulator), will have its settings ignored, right?

I just attempted this to address the earlier poster who was asking for something like a DX7. I agree that trying to come up with something like a DX7 in Fathom will quickly become quite messy.