Rutt-Etra style scan processing with Gen3 modules

Hi All,
Long time reader here, no LZX/modular gear at the moment. I discovered everything during Covid and have not been able to purchase anything since then as everything is out of production or became collector’s gear given the public prices on reverb and all…

As some Gen3 seems to hit the shops, I am still lacking knowledge and therefore having a hard time understanding what modules I would need.

From the LZX patch post for Rutt-Etra style work, here are the modules I am craving for :

  • Visual Cortex
  • Navigator
  • Bridge
  • Passage
  • Shapechanger

Could you guys educate me on how these modules have been translated / integrated in Gen3 modules ?

Many thanks……!


I presume you got this module list from Lars’s post here: A patch for Rutt-Etra style scan processing with an XY display

In the context of Rutt-Etra scan processing, it’s probably better not to look for replacements for the modules, but of the functions they provide in the scan processing workflow. For instance, in the patch, Bridge is being used as two separate functions: amplification and fader (there might be a better term for what it’s doing in scan processing but I don’t know it). Visual Cortex also is being used for a couple different functions (video input and H/V ramp generation). H/V ramp generation is built into gen3 modules that need it, so you might not need that function, but if you do need it separately for this process, you can use a DSG3 Dual Shape.

That said, some do have a fairly direct gen3 equivalent. The gen3 equivalent of Passage is Proc, and I think it can (probably?) be used the same way in that particular patch. I believe Chromagnon is going to have similar functions to Shape Changer and Navigator, though I think at least some of that functionality is also planned for ART3 Affine Morph. There’s been some talk about plans to make a module that will handle the attenuation/amplification aspect that Bridge did, but I don’t think there’s been anything solid yet.

I think that just leaves the fader portion of Bridge and the video input portion of Visual Cortex… I think the fader portion of Bridge could be attained with the FKG3 Keyer. And the video input of the Visual Cortex could be handled with the TBC2 or the Chromagnon (neither is currently released, though we’re all hoping they will be soon!).

Speaking of Chromagnon, there’s a pretty good possibility that the Chromagnon will be able to handle the entirety of Rutt-Etra style scan processing, all by itself with no other modules. I believe I heard that mentioned at some point – maybe someone can confirm. It definitely has several of the required functions built in (including x/y output!), and I wouldn’t be surprised if it also has the others. Assuming this is correct and Chromagnon will handle it all itself, this will definitely be the cheapest way to do it with new LZX gear.

(I should note that when writing this response, I was only considering LZX modules. There may be offerings from some other video module manufacturers that are available and can do some of these functions. If anyone knows of any, speak up, please.)


A quadrature oscillator like the Syntonie VU006 could also be useful.


Would you mind explaining what the quadrature oscillator would do in a scan processor? I’m very new to all this stuff and just don’t know exactly what it would help with in the Rutt-Etra context. I’m actually building a scan processor right now, using a variety of modules from different manufacturers including Syntonie, so I’m wondering if I need one for my setup. Thanks!


Yes, exactly. Dreaming about this for almost two years now.

Yes, sure, this is where I need some help. Many thanks for breaking this down. I’ll just type a quick summary for further reference and/or to make sure I start to understand the process.

Legacy modules and their functions used in this patch :

  • Visual Cortex → Video input + H/V Ramp generation
  • Navigator → H/V Ramp processing
  • Bridge → Amplification + “fader”
  • Passage → Luma Processing (contrast/brightness)
  • Shapechanger → H/V Ramp processing

Functions to Gen3 modules :

  • Video input → Chromagnon + TBC2
  • H/V Ramp generation → DSG3 Dual Shape
  • H/V Ramp processing → Maybe ART3 Affine Morph + Maybe Chromagnon
  • Amplification →
  • “Fader” → Maybe FKG3 Keyer
  • Luma Processing (contrast/brightness) → Proc

Legacy Modules to Gen3 modules :

  • Visual Cortex → Chromagnon + DSG3 Dual Shape + TBC2
  • Navigator → Maybe ART3 Affine Morph + Maybe Chromagnon
  • Bridge → Maybe FKG3 Keyer
  • Passage → Proc
  • Shapechanger → Maybe ART3 Affine Morph + Maybe Chromagnon

Awesome ! Would you mind sharing with us your thoughts on building this rig today ?

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Quadrature oscillators are generally used as 2D path/shape generators (depending on speed). They also make BEAUTIFUL modulation sources. Mixing them with your h+v ramps is one of many entry points to the really fun scanimate-style raster processing effects.


Big caveat that I’m kind of “faking it til i make it” through this. I’ve gotten a lot of advice from a friend who knows way more than I do about this stuff. I’ve mocked it up on modular grid here (the BNC is a placeholder for a simple 3.5mm to BNC 4hp module)
But the basic idea is
Syntonie VU003 for sync and luma extraction of incoming CVBS signal
Syntonie VU009x2 for H and V ramps
Foxing Hour MultB to spread the luma around for various uses
LZX Cadet X x3 for multiplying (still a little fuzzy about where exactly these go in the signal chain, plan to figure it out using trial and error)
LZX SMX3 mixer for doing things like Luma + Hramp or Vramp for that cool Rutt-Etra false depth effect
VH.S Baja for modulation
Foxing Hour Access for final attenuation/fine tuning

@CountFunkula you had me at “scanimate”


VU009 is a VCO, does that work as an alt for ramps?

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Yes, a ramp is just a single cycle waveform that has been synced to either H or V pulses. You can set both the H and V sawtooth waveforms from VU009 to exactly one cycle without a ton of fuss. It also has a built in offset control which is very useful for initial positioning the ramps on a vector display. If it looks wrong, you probably have the frequency too low/high.

VU009 is probably the most direct way to get ramps with the currently available modules.

EDIT: They are being used as the H/V ramp sources in the 5th / 6th videos in this IG post:


I built a Cadet Sync and Ramp just for Rutt Etra when I could have used my Vidiot all along?! lol

I haven’t used a Vidiot so I’m not sure if its oscillators can be tuned to exactly one cycle but theoretically, yes. The exact module doesn’t matter, you just need two sawtooth or ramp oscillators that can be synced to either H or V pulses and tuned to exactly one cycle. Not all video oscillators can readily do this–Prismatic Ray for instance needs external DC modulation to FM it into a single cycle for a H rate waveform and it doesn’t have a native sawtooth or ramp output.

A dedicated ramps module just removes the necessity of tuning the oscillator, dealing with drift or accidentally bumping the frequency pot and losing your patch.


Ramps in the general video sense, yes. However, if you want static vertical and horizontal ramps, you want a module like DSG or ART. Feeding all 4 quadrature outputs into ART will let you do rotations. This is how the Gen2 Navigator module worked - phase quadrature LFO with multipliers and adders. ART gives you the multipliers and adders, plus ramp generators.


You can do it with a vidiot. Just use the h + v square wave outs.
You can even use the rgb ins and the attenuverters for scaling and the rgb outputs Jacks for xyz.


How would you make square waves draw a raster on a scope? Are you multiplying the square wave against the triangle output somewhere?

But yes, RGB interfaces line up very nicely with XYZ signal operations.

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Btw phil baljeu pointed out you need some dummy cables in dsg to get simple h + v ramps.
Was really confusing to patch without this infomtion. You get crazy twisted results if you use it without the dummy cables :sweat_smile:


In my memory i used the square outs without any further processing :sweat_smile: but now i’m insecure if i used diver for the h +v ramps. Have to test it again.

Martijn of Reverse Landfill posted a couple of helpful pictures here:

The 2nd picture has five (maybe 6, I only Weißglut looked) “X” blocks marked, those are the required Multiplier modules, they control the volume of a signal & can be thought of as a VCA (Voltage Controlled Amplifier) if you’re familiar with audio synth jargon.

Ahh, you mean the Cadet X, not the Castle @vidwizard.

There’s another such picture/illustration that shows how the quadrature Osc & its 4x 90° phased outputs bring the various ramp signals in & out to create the rotation effect.


The first post of this lengthy thread goes a long way to explaining the power & use of Chromagnon & it’s relevance to the topic of this thread.

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Yes Cadet! Thank you, fixed.

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A 4-quadrant multiplier is also achieved by crossfading between a non-inverted/inverted version of a signal. Mult a positive signal, put that into side A of a crossfader, then invert that multed signal into side B of the crossfader.


It’s possible to use the Video Calculator from Afterlife Laboratories to do a Rutt Ettra style patch.

The company shared this image with me. They said With Gen3 LZX modules you can use ESG3, and the DSG3 for ramps. I’m not sure how to get CVBS into a luma signal using the ESG3 without the TBC2. I asked but did not (yet?) receive an answer. Does anyone have any thoughts on that?