Fathom Synth Development Thread

[Faiky]

Hey Everett, I'm so happy to see you back at the start, welcome back!
I hope you have enjoyed a Thai massage !
Thanks for adding Hard-Sync, it doesn't sync with another OSC, but you can simulate this effect with it (exactly what I wanted). Great!
I'm really looking forward to the addition of a waveshaper soon, for aggressive distortion or overdrive, softclipping, fuzz effects, I think it's essential for every good synthesizer, for ACID sounds, power leads, etc. Then I pay for the next Thai massage! .

Bugs:
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I still don't get quite warm with the synthesizer, if nothing happens while moving the knobs, do I have this mistake only?
Example: Amount with Wave Table Algorithm. An effeckt is sometimes only audible if I change the algorithm back and forth or change the tabs. I haven't quite understood when this happens and when it doesn't. I might make a video, which software could I use?
When I set the draft mode, the FM sounds also go back, there is no more modulation to be heard. Not until I change the controls again.

Quality:
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FFT filter roll out. The transition from the filter is extremely harsh. The filter itself (because of partial reduction) and the transition from the slide to another frequency is transitionless.
Would be a case for an extended quality setting. Not everyone has this in the audible range. The partial reduction, however, already if this is too low (which is the case with fathom by default).


FM:
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FM is my favourite function on synthesizers and can't be sophisticated enough, it's too often ignored.

- For DX7 support, a second FM function would have to be added first: Phase Modulation. It's already possible in the wavetables, but it would be great if you could switch the form with the two OSCs connected. Two different FM algorithms are a big selling point.

- Ratio Multiply / Ratio Divide is unusual to use. Because also pitch is reset and not taken from the OSC.
Here it would be nice if you could change the frequency of OSC1 and OSC2 separately and synchronize it with the frequency (pitch) in the OSC settings.
I would be for: Freq. OSC1, Freq. OSC2 instead of Ration Multiply / Ratio Divide.

- DC-Offset: A DC-Offset control for the modulator, so you can prevent OSC2 from folding and only allowing higher frequencies than itself.
Remove DC-Offset should be switchable. Exactly this is sometimes desired.

- Antialiasing: Lock to ocatves function. If such a function is enabled, you could use a wavetable in the background to prevent aliasing. It is then a repeating cycle.
For antialiasing between the steps only oversampling might be useful.


The upcoming features sound great!
Thank you for all the sweat, blood and tears you've sacrificed for Fathom!

[FathomSynth]

I have a new release coming out this week so I would like to make sure all bugs are resolved. I have questions about each of your issues here.

Nothing happens when moving knobs? Which knobs?

Wave Table Amount. The results of combining the left and right tables using any of the algorithms depends on the waves in the table, so I have no way of knowing if some effects are more audible than others, or if some can’t be heard, without seeing exactly what you are doing on that page.

Some of the algorithms are pre-calculated so they may not take effect audibly until you lift the mouse off the dial.

“Change the tabs”? Sorry, I don’t know what you mean by “tabs”. You mean the oscillator pages?

Yes, making a video is a good idea, because the wave table page is complex and I won’t know if there is a bug without seeing exactly what you are doing.

Draft mode should not change FM. I’m not sure what you mean by “FM sounds also go back”. Please include this in your video.

“FFT filter roll out. The transition from the filter is extremely harsh. The filter itself (because of partial reduction) and the transition from the slide to another frequency is transitionless.”

Sorry, I have no idea what that sentence means. What is “transition from filter”?

If you are talking about modulating filter cutoff frequencies, then the amount of harshness is your decision.

Yes, I am planning on adding Phase modulation to the FM page.

I can’t change FM Ratio Multiply/Divide because it would impact existing presets for thousands of users. However, I can add an option for calculating this ratio another way if you know of a more standard way this is done. The ratio is independent of oscillator frequency, so I’m not clear what you mean here.

DC offset sounds like a good idea, but I’m not familiar with it to implement it, you would need to provide a web link to an article on the concept.

You will need to create a video in the next day or two, otherwise I won’t be able to get bug fixes into the next release, and you would have to wait until the release after that which will be a while since it will include Intel AVX.

[Faiky]

Okay, that's understandable! I'll make a video at home and exact examples to understand it.

[FathomSynth]

Perfect, thanks so much. That will enable me to get any fixes in this week's release.

[Faiky]

Sorry, my mistake. The bug was the recalculation of the tables, if I change "Amount", there is a lag. But it doesn't happen when the parameter is automated. But it would be nicer if it wouldn't happen while editing.

I updated the settings again according to the instructions, at Reaper and at FL-Studio and now it runs as it should now. Also the resetting of the FM sounds is gone.

The cancellation of the partial tones has also been fixed:

Fathom-Saw.jpg

Sorry, that was in the previous version only (the stereo lane on the top).

Ok here a picture for the filter roll-off / slope:

Filter-Slope.jpg

(Oh, the lower one should actually be further left)

Here is an audible example:
https://www.dropbox.com/s/fzv7bb0ve8t1k ... f.mp3?dl=0

The first tone is a Saw with simply reduced partial tones. Do you hear the ringing? The second one has a small sloping curve, as shown in the diagram above. If we had a setting that added this, that would be great.

[Faiky]

DC offset sounds like a good idea, but I’m not familiar with it to implement it, you would need to provide a web link to an article on the concept.

This should help:
https://docs.juce.com/master/classdsp_1_1Bias.html

I can’t change FM Ratio Multiply/Divide because it would impact existing presets for thousands of users. However, I can add an option for calculating this ratio another way if you know of a more standard way this is done. The ratio is independent of oscillator frequency, so I’m not clear what you mean here.

That's for sure, the buttons have to be kept. But it's difficult to set OSC1 and OSC2 to an exact pitch value. In addition it isn't possible to switch off keytrack-pitch. So you can set a constant Hz number, no matter which keyboard key you press. Like a fast LFO.
I think FM ratio Multiply/Divide is ok, maybe. But the frequency of OSC-2 must be adjustable. How else can I get the tone 4 octaves higher without pressing higher keys?

I'm sorry I didn't check my points. You can now concentrate on the AVX version and have the points in your head for later.

I found a code for a nice waveshaper:
https://github.com/pdesaulniers/wolf-shaper
It probably needs to be translated, but may be a help if you want to do it in the future.

Thank you again! I am very convinced of your project and your work!

[wagtunes]

Just released my library for Fathom.

http://www.wagsrfm.com/fathom/

NOTE: The dev has a smaller library of mine on his site. Those patches are all included in the larger library. So if you've already gotten that library, this library will only give you an additional 90 patches.

[FathomSynth]

Wagtunes, Great job on "Alien Technology". I'm planning on adding 40 more of the presets to the Seaweed Audio version of the bank so it will have an even 200 presets. I just need to get the current release out first. It's been a popular bank so far, several people have purchased it already.

Faiky, Hi, OK I’m glad to hear it is behaving better.

In regard to the dial lag on the wave table page, there is a massive amount of buffer calculations necessary when some of those dials are moved so the lag is unavoidable. In the last release 2.32 I reviewed all the wave table code and optimized those calculations as much as possible, so they have already been reduced to the minimum.

The reason there is no lag during modulation is that everything is pre-calculated for that very reason so all modulations run smoothly in real time, which is why so much recalculation is necessary when the dials are moved.

OK, I understand what you are saying now about the partials roll off. That function is actually already available on the Analog Saw oscillator using the “Spectrum” dial. In a future release I am planning on having that function available on all oscillators. It uses a more gradual roll off than in your diagram, however, I will make a note to create a zone in the top range of the dial which will make the last partials roll off more steeply so you can use it to get the exact effect you were requesting.

In regard to FM oscillator frequency, I’m planning in a future release to enable all oscillator frequencies to be set absolute rather than key driven. This option is available in most synths and I just had not had a chance to do it yet, but it is planned. I think then if this capability was there you could use it for FM in the modulator oscillator.

Which reminds me, folks, I have awesome news, for the next release, FM will have two new settings.

The first will enable you to switch on and off the synchronization of all FM parameters, so you will be able to use different FM parameters for each oscillator in an FM network.

The second is a new FM Tonal Mode. The new toggle allows you to chose either free-running or tonal. In the new Tonal mode the modulator and carrier oscillators are synchronized at the start of every cycle which forces the entire FM sound to remain pitch tonal no matter what the dials are set to. This enables you to modulate the multiply and divide dials with far ranging values and still keep the oscillator tonal. You can use these dials to create exotic waveforms with FM including extreme high frequency content, but without the oscillator deviating from tonal cycles like it does in the exiting free running mode (which will still be available).

Here's a quick demo of the Free vs Tonal FM modes:

https://static.kvraudio.com/files/3302/fmfree.mp3
https://static.kvraudio.com/files/3302/fmtonal.mp3

Also, “Trance Warehouse” will be coming out in a couple months. It will be a super bank of 200 all Rhythm, Sequence, ARP presets for Trance and Rave. It will basically be the most extensive collection of EDM rhythms ever created in a single bank.

[Faiky]

It uses a more gradual roll off than in your diagram, however, I will make a note to create a zone in the top range of the dial which will make the last partials roll off more steeply so you can use it to get the exact effect you were requesting.

Nice! For example, VPS Avenger has a "slope" knob to adjust the slope.
Then you decide for yourself how strong the effect is.

The second is a new FM Tonal Mode. The new toggle allows you to chose either free-running or tonal. In the new Tonal mode the modulator and carrier oscillators are synchronized at the start of every cycle which forces the entire FM sound to remain pitch tonal no matter what the dials are set to. This enables you to modulate the multiply and divide dials with far ranging values and still keep the oscillator tonal. You can use these dials to create exotic waveforms with FM including extreme high frequency content, but without the oscillator deviating from tonal cycles like it does in the exiting free running mode (which will still be available).

That's a dream ! Another point that makes Fathom irreplaceable and unique!

Even at the risk of it being reductive to FM. What about pitch as an algorithm in the wave table oscillator? Simply because of the table advantage.

Sometimes i want to adjust the frequency of the WT osc. under 1 to 0.5 or 0.25 or 0.125, which unfortunately doesn't work. But then so many new possibilities would be open.

Thanks here to my favorite developer! You're the best !

[FathomSynth]

Thanks for your support, that's good to hear.

I agree, adding FM (pitch) as an algorithm to the wave table oscillator would be cool. It would not be redundant with existing FM since using it from the wave table would allow other possibilities such as using the right side table wave to control the amount of FM at the cycle rate and audio rate. I have put that high on the feature list.

Version 2.33 will be out this week, with Tonal FM, still have some testing to do.

As a thank-you to KVR I'm extending the $25.00 sale here through the end of October.

This is a huge discount for KVR members as the normal price on the web site is still $45.00.

[Faiky]

Cool!
Short question:
Why are there 2 knobs for "Ratio Multiply" and "Ratio Divide"? This could theoretically be covered with a bipolar knob and would be easier to handle. So for me personally, anyway.

[FathomSynth]

It started as a personal preference of mine, I would rather enter 2/3 than 0.6666666666666667.

Meaningful numbers in FM for tonal results are whole number ratios such as 1/2, 1/3, 2/3, 1/4, 3/4 etc. The idea was to make it easier to get to these whole number ratios and to modulate on them. Good luck remembering that 1/6 is ‭0.1666666666666667‬

Also using FM as a sub-oscillator requires large values in the denominator such as 1/3, 1/4, 1/6, 1/8 and having to remember what the decimal number is can be time consuming and it's easier just to set the divide to what you want.

[AdvancedFollower]

When I go to https://www.fathomsynth.com/ and click Upgrades, then "BUY THE LATEST 2.32 UPGRADE" I get to an error page, "We couldn't find the page you were looking for."

Edit: It seems to work if you go to the "Buy" link at the top of the page and then add the upgrade to the cart via the Buy Direct button. It's only the link on the first page that's faulty.

[FathomSynth]

Oops, that was a dead link, thanks for reporting it, it's fixed now.

The discount sale is only here on KVR.

[PointOfDeparture]

How do you get the discount offer? I didn't see it on the Seaweed Audio site.