All, here is the (mostly final) proposed version of my rack. I'm a noob, so please tell me any oversights or mistakes I might be making.
ModularGrid Rack

I wanted a starter system with room to grow, largely composed of well regarded, easy-to-get modules.

Notes:
* It uses Synthrotek's Powered Waterproof 6U + 1U Portable Eurorack Case, with 2 x 84hp of Euro, and 1 x 84hp of tiles. This should provide plenty of power and depth, even for the DuaLFO.
* The Euroduino is supposed to run a custom sequencer that I intend to write (I'm a brand-new wiggler, but a pretty good programmer). The Cloq will provide the basic clocking, and the Euroduino will control the Befaco VC Slew Limiter for constant-time slew between notes.
* I'm most-likely going with the Orgone Accumulator. If so, I will commission it from synthCube. I am not a DIY guy yet.
* Have 2 1U tile Noise sources for really basic percussion, with a simple EG coming from the Strike input of the Optomix.

Questions:
* The oscillator was by far the hardest decision to make. I like the big sound of the Orgone Accumulator, and it seems to work well with a smaller system (a reasonable number of CV ins, and only two outs). The Dixie is primarily there for modulation duties. Any other suggestions?
* Is the Pittsburgh Low Pass Gate a good match for the Accumulator? Or should I go with a traditional filter?
* Should I wait for the PulpLogic 8U 'Magnum' lunchbox case, whenever it comes? (2x euro @ 96HP, 2x tile @ 96HP). It is vaporware, as far as I can tell.

Thanks for your input!
-Ken


Looks good, but as always, there should be some more VCA?
Interested how you will do the Euroduino sequencer, with only two knobs and 8 sockets ...


Thanks for the feedback. The early response on Muffs made notice of that too, so it looks like I will need to add a dual VCA, and probably a mixer.

Regarding a sequencer program, the Euroduino has four outs: two gate/triggers (which I will call D0 and D1), and two 256-value CVs (CV0 and CV1), which I imagine have a kind of stepped output.
So, my initial thought on output mapping is:
* CV0 = Pitch
* CV1 = Rate (the absolute voltage difference from the last pitch)
* D0 = Gate out
* D1 = Trigger out (start of Gate)
Which, from what I've seen, is pretty nice for a basic sequencer.

Now, on to the inputs. The Euroduino has 8: 2 pots (P0 & P1), 2 a/b/c switches (SW0 and SW1), 2 CV ins (IV0 and IV1), and 2 digital ins (ID0 and ID1).
If you think about all the knobs on a typical sequencer, this is a very limited interface. So, one has to make compromises, or be prepared to think differently about how a sequencer should act. I'm not patient enough to program each individual pitch through this interface. The cheat I make is letting the device choose these values for me.

For consistency, I have mostly mapped '0' controls to duration, and '1' to pitch:
My initial thought on the input mapping is:
* SW0 = Duration mode (a=random, b=euclidean, c=darwinian)
* SW1 = Pitch mode (a=random, b=tbd, c=tbd) tbd = some pitch algorithms that sound more organized than random.
* P0 = Duration continuous variable, based on SW1 (a=bit crush,
* P1 = Pitch continuous variable, based on SW0 (a=bit crush, b=tbd, c=tbd)
* IV0 = Either CV for P0, or Spread (duration range)
* IV1 = Either CV for P1 or Center of pitch - roughly a transpose
* ID0 = Clock in
* ID1 = Toggle of mode - repeat or continuous, etc.

This is a rough sketch, but still probably way too much detail than you were expecting.

Basically, I am thinking about a mini sequencer framework, with interchangeable functions for Pitch and Duration.

Any thoughts?


I see, some kind of intelligent/macro sequencer. Seems like a lot of work.
While I am generally very interested in microcontroller coding I found out that it is just another distraction from just making music so I try to stick with the modules other people came up with :)
Anyway, best luck with your project!


I'm unclear with why you need to code up a custom sequencer. And agree with @solitud's comment that it will take away from the music making aspect.
Look into MI's Grids (programmable as well).


@solitud: I have had this debate with myself as well: why program all day for work, then come home and code for fun? I guess there are two (maybe not very good) reasons: 1) my interest in Arduino programming is high right now; 2) I don't expect to be making Music for quite a while (I'll be mostly irritating the wife/friends/dog, especially at the start).

@mt3: The reason is my perception of the lack of acceptable alternatives at a decent price. Cheap and narrow = inflexible, while wide and complex = expensive, plus hogs too much space on my starter rig. For instance, Grids is an impressive module, but it doesn't offer 1V/Oct out.

Looking at what I do well, maybe my best opportunity to contribute to the community is through code.


@solitud: I have had this debate with myself as well: why program all day for work, then come home and code for fun? I guess there are two (maybe not very good) reasons: 1) my interest in Arduino programming is high right now; 2) I don't expect to be making Music for quite a while (I'll be mostly irritating the wife/friends/dog, especially at the start).

I don't wanna talk you out of it, I am pretty much in the same boat and even developed a module based on Atmega myself.
Modular synth is a hobby that goes way beyond making music for me. The community chats and never ending optimizations of systems are an integral part of it.
You just have to prioritize at one point since time is sparse and you can not do everything.
So if you wanna do your own sequencer, at least make it kick ass.


Oh ... you're the 'Ultima Ratio Cascading Clock' guy! That's an awesome-looking module!

I looked at that one closely, but it seems to function best with an external clock. What do you use for a clock generator?

I'm trying not to front-load too many obstacles to a successful start-up rack, which is why I'm trying to avoid too much DIY, but I did read through the build document, and it looked reasonable. Maybe not as simple as the Super Warp Generator, but pretty approachable.

Do you still have kits available?


Oh ... you're the 'Ultima Ratio Cascading Clock' guy! That's an awesome-looking module!

I looked at that one closely, but it seems to function best with an external clock. What do you use for a clock generator?

It works fine as a clock generator, you just loose the ability to control one of the two dividers in clock generator mode.
As an external clock you can nearly throw anything in it, a square wave from an oscillator works best.

I'm trying not to front-load too many obstacles to a successful start-up rack, which is why I'm trying to avoid too much DIY, but I did read through the build document, and it looked reasonable. Maybe not as simple as the Super Warp Generator, but pretty approachable.

Do you still have kits available?
-- kismert

I have a couple left. While the build is pretty easy basic knowledge in soldering can not hurt.
I plan to sell some of them next year as pre-build modules.