Chromagnon Synthesis Concepts

Ahead of a demo video to show what Chromagnon can do, and in response to questions about how it works, here are some notes from Lars about the new LZX standalone synthesizer.

So to explain it compositionally, in a no-input case, it starts with ramp shape selection as the “scene”. You reach over to the right, set it to “triangle ramps” or whatever you like and then you select “Vector” if you want to process the ramps natively or “Shape” if you want to process them as a quadrilateral (4 quadrant mirrored AKA triangle ramps) space. Then you have XY controls, edge softness, etc. like a typical Navigator/Shapechanger based patch.

To change that shape, you modulate it either directly (with ambient motion generator or directly patched source) or you use the Modulation Vector, which allows you to define a 2D rotation for the ramps in parallel and then use that to displace the original ramps thru a mod matrix (the 5 buttons on the lower left). Imagine if you had a 2D staircase and that 2D staircase had dual VCAs feeding the rotation angle of Navigator–that’s what the Modulation Vector section is.

Now if you want something a little more wiggly, like an oscillator pattern, that’s what the “Fold” button does (Fold button on = Super Staircase = Chromagnon is complex shape generator).
Fold will add more density to the pattern (like Staircase does), whereas fold off allows for dimensional displacements (like this is where you’d patch luma for your Rutt Etra effect).

Right side buttons in order…

  1. HV/Ramp shape select (8 ramp shape options)
  2. XY Mode – this sets the main function of the instrument: Chroma gen/proc, Luma gen/proc, Vector (for ILDA or XY displays), and HV (for shape/pattern generation with ramps)
  3. Luma output source (these go thru a YUV to RGB converter, and then into the Porter-Duff Compositor as the Top Layer/Foreground)
  4. Chroma output source
  5. Porter-Duff Compositor (12 modes). These settings change the way the processed output and the input source are blending together, like a wet/dry composite. There’s a lot of analog logic and dual key generation trickery here, to achieve the complex RGB logic.

To break down button 2 a bit more, you can think of it like 4 different patches. You effectively have two modes for external source processing (Luma and Chroma), one mode for pattern synthesis (HV), and one mode for vector/laser synthesis (Vector). It changes the context in which the signals interact. Vector and HV mode are almost identical–just different ramp settings and VCA/Gain strategy. For example, in Vector mode Edge controls raster size. In HV mode, it is a high gain clipping function.

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so this is the layout for the keying section display?

there are 8 hv ramps (HV>),
4 described “patches” (>XY),
and 12 modes for the porter duff compositor (RGB>)
that leaves 3 options for both DST LUMA (XYK>) and DST CHRO (>RGB)

in the signal flow both the DST LUMA and CHRO have 3:1 mux

with the names of the buttons would make sense

luma
key, shape and max (assuming that is the 1v white)
chroma
src, xy, and none (assuming that is the 0v black)

I’m feeling some wheels clicking into place about this layout

it seems like this trick (seen in the video below) I stumbled onto the other day with the v440 mixer and switching between two sources luma/chroma combinations was not a coincidence but maybe mental preparation for chromagnon

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I was looking at this and thinking a similar thing just a few weeks ago. I didn’t bother working out all the details, but I realised a Chromagnon would work better for me than a whole lot of other modules and/or external devices, like a V440. Every time I look at that mixer, I come to the same conclusion. This signal flow/generation/processing explanation confirms it. Thanks, Lars.

However, the real big selling point, for me, is the power and case. Clean power with a stand-alone case wins. If I can also rack it on 84hp rails, that’s another winning feature. Chromagnon looks like it has all of that, but I’ll hold back my excitement until its available from a UK shop.

Thanks.

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Neat!
Any idea when the first video will drop?

The first video will drop after a complete Chromagnon unit is finished and delivered to Johnny Woods. Right now the team is finishing TBC2.

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Super stoked! I’d love to make some examples too when my first day pre-order arrives. :smiling_face_with_three_hearts::vulcan_salute:

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So helpful! The anticipation has been stoked.


Q: What is this modulation vector?
A: “That’s “orbital displacement.” The modulation vector has Sin/Cos output, so if you feed an LFO then orbital displacement will cause the shape to position itself around a circular path. You could do something similar by feeding a quadrature LFO sin/cos into Navigator XY. Or using navigator 1 out to modulate XY of navigator 2. Something that’s not implicit from the panel is that there are four states for each modulation vector button. off/red/green/yellow = off/x/y/both.”

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A note on Chromagnon’s video i/o:
It will support “240p/288p/480p/576p/720p/1080p30. We could even add some timing profiles to match some weirder formats as well. On the rear we have an 8 position dip switch. 1 switch turns sync auto-detect on/off – with it on, system genlock switches to match the format of the TBC input source if no sync input is present. Auto-detect is always on for the sync/genlock input, and that overrides any TBC input source. The other 7 bits select up to 128 different video standards. So in the case of using Chromagnon with no input, or as master sync gen, you will select your default video format with these switches.”

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1080p video feedback possibilities ermahgerd!!! Can’t wait. :smiling_face_with_three_hearts:

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Does this mean it will sync to arbitrary rates that fit the data rate but are not specified? If not I would love to see standard SMPTE rates like 24p, 23.98p, 29.97p, 59.94i, 59.94p

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I wasn’t familiar with “Porter-Duff”. Upon googling I found this image (it happens to have 12 examples :slight_smile:)
download

Will most of these compositions be essentially possible?

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This corresponds with the 12 compositor modes available in Chromagnon.

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Thanks for clarifying, very exciting!

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Lars, quoted from FB comments, says:

The number of frame synchronizers in a system you need is equal to the number of input sources minus one. So with Chromagnon + Visual Cortex, you can have two external sources. One is the master timing reference, and the other is frame synchronized by Chromagnon’s TBC. Key to the Automata series concept is that all units include a TBC and a 2:1 RGB function. Meaning each device can mix itself into an external source. RGB inputs are separate from the decoder/TBC section. Yes, you can feed the outputs back through the TBC in feedback mode while still using the RGB inputs.
Visual Cortex locks itself to the timing of an external source. That external source can also be fed to an input decoder, so you can patch the video through the system. Visual Cortex has to slave itself to the external timing in order for this to work. Chromagnon locks itself to the timing of an external source via the genlock input (or not, can be free running). Where it differs is that the input decoder has a TBC/frame sync this time. So the external sync/genlock source and the external video source don’t have to be one in the same. Meaning we can sync Chromagnon #2 to Chromagnon #1, while both of them can frame sync an asynchronous external video feed, resulting in two synchronous external input channels. So technically Chromagnon has two external inputs (Genlock/Sync Input and External Video inputs). Whereas Visual Cortex only has one (Input Decoder and Genlock/Sync Generator must be the same).

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so with a visual cortex, chromagnon, TBC2 setup you could have 4 external sources?

Correct. TBC2 and Chromagnon share the same video input platform.

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oh wow things are going to get wild

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^Agreed!! Had to jump on the pre-order bandwagon!!!

It’s stated that the chromagnon will replace the functionality of the polar fringe, yet no joystick, I’m not all too sure about how this will work. So I’m wondering if this is going to be built in to the modulation section. Also does this mean an eventual discontinuation of polar fringe?