I have removed two modules I never/seldom use so now I have 10 HP free space.
I will fill this space with modules that can help me improve my generative patches. So I would be very pleased to get some tips which modules I should choose.
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triple sloths and a blank 2hp panel
a 10hp matrix mixer

Thanks for the advice!
Never heard about the Triple Sloths and I do not understand how to use it. But I will check it out and try to understand how it works :-)

Triple Sloths is from the Nonlinear Circuits lineup. IMO everything in their Chaos lineup of modules is very interesting and I intend to add more than one of those to my system in the next 6 months.

To my understanding, the Chaos type modules are basically an alternative to random modules. Some would say (and I would agree) that in general random is not very musical; the main use case I have for random is adding a small amount of it to various parameters. Chaos, on the other hand, is loosely patterned -- imagine for example a drunk person riding on a bike going around a figure 8 track; they follow the track, but not exactly. This type of loosely patterned behavior, many people including myself would consider musically useful: it is repetitive enough to indicate some type of cycle, but loose enough to never repeat strictly, and hence keep generating interest. My intended use cases for the Chaos oscillators is to add some "slop" to my other parameters, and combine it with other tighter LFOs to get a looser complex mod signal. Not so different from how one might use random, but IMO a bit more useful due to its semi-patterned behavior. There are surely many other uses for these types of chaos modules. To my knowledge, Triple Sloths gives 3 "chaos" signals ranging from slow, slower, to very slow.

BTW many other modules from that manufacturer look interesting (if somewhat baffling) to me.

Good luck, enjoy!

I did this a bit differently. Instead of just fixing the gap, I opted to whip up a potential "destination" rig. But since the rack space is really constrained (2 x 88 [not 89!] hp), what I wound up doing is to shrink things down across the board so that you can get a lot closer to a true generative rig.
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I tried to keep as much as was possible here, but several devices got chucked out in the process. One of the first to go was the buffered mult; since you'd use the VCOs separately(ish) in generative work, and also because it stole 4 hp, it became unnecessary here...and tbh, in a small build like this, mults in general should be avoided as they rob space from function. Use inlines instead.

Top row: Starts with the P/S, of course...then the Disting, followed by the quantizer (I presume this is for quantizing modulation curves, which is a basic generative technique), then all four sources. After these, one of the Veils (I resized both to the new model) for level control before filtering with the Ripples. Then I placed the Xfader after this, as it offers an interesting opportunity to set up autopanning. The Doepfer mixer is next, then there's all of the effects modules, followed by a Happy Nerding OUT. Now, the reason for that specific output module (aside of the transformer isolation) is that it fixes several problems. For one thing, it gives you a headphone preamp. But much more importantly, it has a second input pair...which then allows you to split the mixer's output between the Verb and the Monsoon, and then you can fly one of those in over the other via the second input. Also, the ganged stereo controls here are definitely easier to balance than the separate controls on the Doepfer passives.

Bottom row: A 2hp Nse first, because there weren't any noise sources for the Marbles to play with. Then the Marbles itself got smushed down to a Pachinko...same module, more or less, minus a few hp that gets used elsewhere. And one of those places is the Quad LFO next to it; to really have a decent generative setup, you NEED extra utility LFOs to provide modulation curves that other modules can reprocess. Maths, Veils, and then a little Frap 321, which allows you to attenuate, INVERT, combine, add offsets, etc. It's pretty much a modulation mangler, allows you to generate more complex modulation results. Then a dual ASDR is after this, giving you a couple of 4-stage envelopes for your audio chain, etc. Then the cryptic-looking thing that's next is a dual window comparator...and THIS is definitely the missing link for generative work. Comparators generate gates under specific voltage input conditions...so, say, an LFO is patched into one and the comparator's threshold is set for 3.5V. The comparator will output a gate each time the LFO's output exceeds this, meaning that you can also use your modulation sources as on/offs for signals that are thruputted through VCAs. But this is no normal comparator, but a WINDOW comparator...meaning that it has TWO thresholds, and you can get gates and triggers when the input is below both, between both (the "window") and above both. This way, you can derive several possible signal states from one single modulation source...and of course, since you have TWO here, well... Anyway, speaking of derivation...the next thing is exactly that, a Derivator. This module also fires off gates...but this time, they're dependent on the direction of the CV that's being inputted. So on this, you have gate-outs for "rising", "falling", any sort of movement at all, or "steady". Now, if you're wondering "why all these effin' GATES?"...the next module answers this. Yep, a Boolean logic module...but this one's a lot more capable than the original Ladik one, as ALL of the gates are usable simultaneously. So, with all of the gate outputs based on CV/mod behavior, you can then take "steady" gates and use the Boolean module and combine everything in those, and get a WILD panoply of possible off/on activity. And to make that even more bonkers, the thing after the Boolean module is a dual probabilistic pulse skipper...so you can actually have random(ish) dropouts in your controlling gate signals. Coupled with logic, like here, that's a potent module. And then the clock divider ends things up.

Now, look closer. You'll notice that, in my build, there are a lot of modules that depend on other modules...and not necessarily the SAME modules each time. For instance, you could use the Skipper for the Minibrute's clock output, keeping things in the modular in pace...except for those odd little "hiccups" that also cause their own strange things to happen, or you could just as easily use one channel of it to randomly "suppress" control gates from the Booleans, and so on. THIS is how you do generative...it's not a matter of "patch A to B and turn knob" at all, but a system that contains LOADS of complex possibilities depending on how it's patched, plus in this case, you have to factor in the Minibrute that's being augmented by the build. IMHO, this does that pretty well. But no, it doesn't use everything you have presently AND it uses some things you don't have on hand. Like I said, it's a "possible end-result" build. Hopefully it's of SOME help.

Thank you nickgreenberg for the sloth explanation. It seems to be a very interesting companion to Marbles that is my main random source.

Thanks again Lugia for taking your time helping me. Much of my current rack is a result of your earlier advice and I like it a lot.
Your suggested remake of my rack seems to be a killer (small scale) generative machine. I will carefully evaluate the new modules and replace my old modules one at a time. But there are so many of my current modules that I have to skip so I must try to sell them before I can buy new ones.
If I don’t find any buyer I maybe go for one of my earlier ideas; getting a small skiff where I can put them.
I really look forward to plan my new rack!

If I don’t find any buyer I maybe go for one of my earlier ideas; getting a small skiff where I can put them.

-- Rookie

cough cough - leave room for expansion - if/when you buy another case, buy one that will house all the modules yuo have as spill over and then some - I'd go at least double the size you think you need - otherwise the need for the next case will arrive sooner than expected!!!

You are absolutely right JimHowell1970.
My rack is to small. But when I started my intention was only to add som functionality to my Minibrute 2S, not going deep into modularity. But then I get caught and are now module dependent.
And what I have heard there is no cure for this kind of addiction ;-)

I read the manuals, check reviews and look at the Youtube videos about the modules you have suggested.
I think they will be a great improvement for my generative struggle.
But there are two issues in your comment that I dont really understand.
1. How shall I use noise for modulating Marbles?
2. How to use the quantizisised modulation curves?

OK. let's go over these questions one at a time...

1) Noise can be used with Marbles in a number of ways, besides the point that it's useful for a number of other purposes...both modulation AND audio. But as an example, let's take the "jitter" input. By introducing noise at varying levels through this input, you can increase the instability of the Marbles. But there are loads more possible than JUST that. Suffice to say, noise is pretty essential in general in ANY synth, and there's tons of points in the build where a totally random source of that sort would be useful.

2) By using the Penrose quantizer. What you'd do there is to define a set of notes that fit the overall musical scheme you're working with at the time, then feed a modulation source into the "Input" and a clock pulse to the "Trig". The trigger fires the sample and hold circuit in the Penrose to lock in a single voltage value from that modulation curve, then the Penrose "rounds" that value to the nearest assigned scalar step. By using very sparing clock pulses (Skipper at, say, 3/4th of maximum stochastic skips) to add harmonically related blips every time the voicing connected to the Penrose fires.

When you consider what's going on there, it's really very sample-and-hold-like...but the resulting control voltage values get constrained to ONLY the ones that you've defined, not totally random values.

1. Never tried to use noise with Marbles but now I will :-)
2. This is a new way for me using the quantizer. Very interesting.

Also keep in mind that the Penrose will quantize ANY incoming voltages, just like any other quantizer. You could just as easily input a fixed offset voltage, controlled by a knob, and you'd be able to "play" the offset, which is useful for setting up drones and being able to then transpose those with the offset knob. But the Penrose's ability to user-define scales means that your knob-twists will ONLY fall into the designated pitched programmed into the quantizer.

This ability to "force tuning" is one thing that makes quantizers...especially scale-definable ones...super-useful for generative work.

My goal is to build the rack suggested by Lugia.
But I have to do it in steps.
1. I remove the buffered multi (4 HP). Now I have 14 HP free space.
2. I add Doveman SHFT (6 HP), Ladik Derivator (4 HP) and Ladik Skipper (4 HP).

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4. ”Shrink” Marbles, Plaits and Veils plus removing modules for making space for the rest of the suggested modules.
What do you think?