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Wavetable Waveform Split Points

chysn

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Wavetable Waveform Split Points
« on: December 23, 2020, 07:06:24 AM »
As we all know, the Pro 3 wavetables have 16 "reference waveforms." But each waveform is represented four times inside the system exclusive data, and the waveform among these that the Pro 3 actually uses is based on which key is being played:

(1) One 1024-sample waveform
(2) One 512-sample waveform (begins around F2)
(3) Two copies of a 256-sample waveform (begins around F3)
(4) Eight copies of a 128-sample waveform (begins around F5)

I say "begins around" because there seems to be sort of a morphing from one waveform to another around that split point. Also, I'm just using my ears, so you might perceive the split point to be slightly different.

There are three wavetables attached to this post. Each one starts with a sawtooth waveform in the 1024-sample data, and then changes to a square for the 512-sample (sq2, #35), 256-sample (sq3, #34), and 128-sample (sq2, #33) data. If you load these and play up the keyboard, you can hear where the changes happen. Note that the data is identical for all 16 reference slots in these proofs-of-concept.

This adds an interesting dimension to Pro 3 wavetables. Acoustic musical instruments change their harmonic content depending on pitch, and Pro 3 can imitate this, to some extent.

For me, I'm going back to the lab on how I'm designing my Pro 3 wavetable library, as I want it to be able to take advantage of the Pro 3's 64-waveform reality, while keeping things simple for normal 16-waveform generation.

I'm going to work on a 64-waveform wavetable that uses an acoustic piano at various pitches, and then I'll have a better idea of whether this is worth the time in practice.
« Last Edit: December 23, 2020, 07:09:31 AM by chysn »
Pro 3

Previous: Mopho Keyboard, Desktop Mopho, Evolver, DSM01, DSM03
Software: macOS, Ableton, MuseScore2
GitHub: https://github.com/chysn

chysn

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Re: Wavetable Waveform Split Points
« Reply #1 on: December 23, 2020, 03:15:45 PM »
When Osc 3 is used as an LFO, it seems to observe only one change, at the 512-sample waveform. This change seems entirely phased in around the C3 frequency. The 256- and 128- sample waveforms appear to be unused in LFO mode.

The split makes it a really unique sort of LFO, one that can be something totally different depending on its frequency.
« Last Edit: December 23, 2020, 03:22:40 PM by chysn »
Pro 3

Previous: Mopho Keyboard, Desktop Mopho, Evolver, DSM01, DSM03
Software: macOS, Ableton, MuseScore2
GitHub: https://github.com/chysn

Re: Wavetable Waveform Split Points
« Reply #2 on: December 28, 2020, 06:35:32 PM »
Hi chysn; How are you? :)

Interesting what you say, I only partially understand this said. Is it possible to have a simplified version?

Since I want to use the pro 3 wavetable efficiently, I think your approach deserves to be deepened.

You talk about 64 ... and that depending on the pitch ... in short, I cut. Is it possible to have a new explanation, I would like to do some tests on my side

Thank you

__ FR
Salut chysn  ;D comment va ?  :)

Intéressant ce que vous dites, je ne comprends que partiellement ceci-dit. Est il possible d'avoir une version simplifiée ?

Comme je souhaite exploiter la table d'onde du pro 3 efficacement, je pense que votre approche mérite d'être approfondie.

Vous parlez de 64... et qu'en fonction de la hauteur de note... bref, je coupe. Est-il possible d'avoir une nouvelle explication, j'aimerais faire des tests de mon coté

Merci
Paper & Pencil

chysn

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Re: Wavetable Waveform Split Points
« Reply #3 on: December 28, 2020, 08:12:15 PM »
Interesting what you say, I only partially understand this said. Is it possible to have a simplified version?

I'm not sure I can simplify it. Each of the sixteen reference slots contains a set of four different waveforms: a 1024-sample version, a 512-sample version, a 256-sample version, and a 128-sample version. Which waveform is used to produce sound depends on the key being played. There's no reason, aside from convention, that these four waveforms need to represent the same audio spectrum.

If you try the three wavetables attached to the original post, and play up the keyboard at different octaves, it will be pretty clear what I'm talking about. It's really easy to tell the difference between a sawtooth waveform and a square waveform.
« Last Edit: December 28, 2020, 08:15:09 PM by chysn »
Pro 3

Previous: Mopho Keyboard, Desktop Mopho, Evolver, DSM01, DSM03
Software: macOS, Ableton, MuseScore2
GitHub: https://github.com/chysn

Re: Wavetable Waveform Split Points
« Reply #4 on: December 29, 2020, 06:58:59 AM »
I totally experienced this with my testing of the juno wavetable yesterday. I can distinctly hear when the changes occur up the keyboard...it was subtle, but quite noticeable for myself.
Sequential Pro-3, Elektron Analog Heat MK2, Elektron Analog RYTM MK2, Elektron Analog Four MK2, Pioneer Toraiz SP-16, Behringer TD-3, 104hp Modular Synth w/Mutable Instruments modules, 48hp Modular FX box with Intellijel Rainmaker and Audio I/O, Eventide H9 MAX

chysn

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Re: Wavetable Waveform Split Points
« Reply #5 on: January 03, 2021, 09:47:08 AM »
After spending the weekend making various types of multi-dimensional wavetables, I've found that the sweet spot is a 32-waveform wavetable with the 1024- and 512-sample wavetables being the same, and the 256- and 128-sample wavetables being the same. The split point at F#3 is musically useful.

One application is having an active wavetable in one half, and a static waveform in the other. The attached wavetable is a demonstration of this. The low half of the keyboard (up to F#3) is a rhythmic bell-type wavetable. The upper half is a static saw-ish waveform.
Pro 3

Previous: Mopho Keyboard, Desktop Mopho, Evolver, DSM01, DSM03
Software: macOS, Ableton, MuseScore2
GitHub: https://github.com/chysn