Zebra 3 Public Beta Revision 20399

[jtsterays]

I'm uneducated, what are the advantages of LPGs? AFAIK it's just filter with a built in env as a single module?

They are an economic choice. Not only are they cheap to build (even if Buchla's pricing scheme suggests otherwise), but they also wrap VCF, VCA and envelope into a single, simple module. The usage as all 3 is limited, but it sounds good for many percussive instruments.

So a LPG typically has 3 operation modes: LP, VCA and LP+VCA. A single knob controls both cutoff and VCA. So they are always linked.

There's one input and output for the audio signal, and another for the cutoff/VCA. Some manufacturers add more features, such as trigger inputs or resonance control.

Because the circuitry uses photo resistance ("Vactrols") instead of transistors, the control signal is smoothed with the characteristics of LEDs: They go bright quickly, but then have some after glow when the current drops. The longer current was up, the slower it drops. Short pings create fast decays, long gates can result in seconds of decay. LPGs with trigger input turn this into a reliable envelope often compared to the envelope of a Bongo.

Like the Minimoog envelopes on short Attacks, LPGs "stack up" when triggered fast. This sound every alive and dynamic.

All in all, they are just super useful and quick to work with, and in a modular environment, an LPG lets one add a complete voice by tapping some oscillator here and a trigger there.

The hottest thing on the market is the aforementioned Natural Gate. It's a dual channel LPG which has independent control for Decay and VCA/Cutoff, plus 3 different "character" settings. It's got the snappiest sound for all the typical applications and very well balanced parameter ranges.

We have no plans to make a digital copy of the Natural Gate, as this is a contemporary unit. We want to focus our emulation skills on vintage units that are otherwise lost.

Thanks for the info. I can see how they are very useful in the eurorack world. But I fail to see how this would fit into Z3 or any of your products. The only benefit I could think of if it was in Z3 for example that it would save an env, but at that point why not just add another env you know. The envs can already do the Minimoog thing, so I'm definitely missing something here.

It would make perfect sense as a VCV Rack module, though.

[Urs]

Yes, but they also do have a sonic characteristics that many people like. I get why they would like to see our take on this, but I agree that Z3 may not be the best playground.

I am thinking about integrating their specific behaviour into the normal Z3 envelopes. This was part of earlier beta versions, but it was not yet convincing enough. Maybe we bring that back at some point, not sure. Once the envelope works, it's not far off from combining it with a filter to achieve LPG-like results.

[pkolsung]

Would it be possible to add a "Constant" or something similar to the modulation sources?
Useful for stuff like setting a specific OSC phase offset without having to use a MSEG, Mapper or precious Macros just for that (or, alternatively for this, just maybe add a phase offset dial in the oscillator window?). Nice to be able to set to get a certain snap out of low frequency stuff like kicks and impacts etc.
I know there is a Rotation tool in the oscillator editor, but that is a little bit too much work. Especially if you use some in-between curve or want to cycle through the curve set/wavetable to find the best position.

Constant could potentially also be nice in conjunction with the Math modules to scale stuff in various ways. But would probably require some sort of control panel in this case, I guess. Or maybe just a little dial on the ModMath control panel to set it whenever it is selected.

--
It would also be nice with an option to edit all the curves in the set at once. At least with certain tools, like the Rotator (a way to address the phase offset "issue" above?) and warp tools.

[Urs]

Would it be possible to add a "Constant" or something similar to the modulation sources?

Yep.

[PieBerger]

Would it be possible to add a "Constant" or something similar to the modulation sources?

In the meantime, you can assign Alternate as a mod source with the Full wave + modifier enabled

[GruvSyco]

Since LPGs keep coming up, my favorite is the make noise lxd. It’s pretty cool in that you can chain one side into the other (12db side and 6db side). When attached to attenuators it has an extremely cool resonance that kind of controllable.

[stippenstoh]

I am thinking about integrating their specific behaviour into the normal Z3 envelopes. This was part of earlier beta versions, but it was not yet convincing enough. Maybe we bring that back at some point, not sure. Once the envelope works, it's not far off from combining it with a filter to achieve LPG-like results.

I think that would be super cool, was the reason you excluded it that it sonically wasn't convincing yet or technically?

[Urs]

Wasn’t any obvious effect.

[pdxindy]

Thanks for the info. I can see how they are very useful in the eurorack world. But I fail to see how this would fit into Z3 or any of your products. The only benefit I could think of if it was in Z3 for example that it would save an env, but at that point why not just add another env you know. The envs can already do the Minimoog thing, so I'm definitely missing something here.

It would make perfect sense as a VCV Rack module, though.

Because with the LPG, you get a set of pleasing behaviors without having to make any complex modulations across multiple parameters. It just works.

[GruvSyco]

It’s the resistive opto-isolator. LPGs get there natural feel literally from light. Fascinating bit of kit actually. I read up a lot on this when trying to source Vactrols for a Buchla clone I was building.

[jtsterays]

Could you guys add a bypass option for the modulation boxes in the modules? Maybe right clicking the double arrows to bypass it or something. Very helpful for learning purposes. You can mute the modulations in the matrix but not here.

[Urs]

Could you guys add a bypass option for the modulation boxes in the modules? Maybe right clicking the double arrows to bypass it or something. Very helpful for learning purposes. You can mute the modulations in the matrix but not here.

Yeah, that's a frequent request. Can't promise quick relief, but it's on our radar.

[ffx]

I am really missing individual outputs... For example, using the very nice preset "Detroit Exploit", it's a multilayer drum loop. Now I would like to process the hihats individually, outside Zebra. Not possible.

So I would like to suggest that you also can select output 1/2, 3/4, 5/6, 7/8 here:

Bildschirmfoto 2026-01-09 um 09.37.37.png

And here:

Bildschirmfoto 2026-01-09 um 09.37.44.png

[PieBerger]

On the topic of outputs, it would be nice if the SEND M/1/2/3 icons doubled up as mute buttons.

[ffx]

Regarding the modulation overview, if you start with "Detroit Exploit", you actually see zero modulation connection, what is modulating what. IMHO this is not very good UX so far, you should be able to see "intuitively" the modulation connections. For example, on mouse-over with a delay:

- a module in the matrix could give a summary of what's used as modulation sources inside
- a knob could give a list of sources, including an amount slider, on/off toggle, and realtime visualization of the amount/speed of the modulation
- the mod source tabs could show a list of targets.

On hover, the targets / sources could be highlighted.

etc.

So currently it's quite difficult to understand the routing in this patch.

It get's even more complicated, because the direct modulations are not listed (at least as immutable elements) in the matrix, so a) you have to look at each slot, and then also have to look at each single knob with a direct modulation option!

Please, maybe step a bit away and try to have a look on this GUI from a pure UX perspective, being a DAU user. I've the impression that you got a bit blind by seeing it every day or something