Konversion

Religious conversion is always a dicey topic but I’m willing to give it a try.

To remind you, I’ve been building a small Eurorack system since early last year. I have twlve modules built with another two in the queue.

A remark three weeks ago from Trevor Pinch prompted me to do some thinking about one of Eurorack’s attributes which I find problematic — its tendency to squeeze everything into as narrow a module as possible, leaving you with tiny knobs and other controls on tight spacings. This came soon after I started following the Look Mum No Computer forum with others who build modules in the more expansive Kosmo format, and after I started thinking about what I’m going to build to house more modules now that I’ve basically filled my first case.

The confluence of these leads to the question, should I change formats? That’s always a fraught thing for anyone to contemplate. For one thing, you’ve made some kind of investment in one format and you hate to lose that. That’s particularly relevant if the change is to a format whose signal and/or control voltage conventions differ.

That’s not the case between Eurorack and Kosmo, and you can freely plug modules of one format into modules of the other provided you have a way to go between 1/4″ and 3.5 mm jacks and plugs. (Well, to the same extent as you can between Eurorack modules — different designers do have different ideas about, for instance, what voltage should correspond to the note C4.) And Kosmo uses a ±12V power supply, like Eurorack and unlike most other formats, and even uses the Eurorack power header (in the 10-pin, non 5V form).

That makes interoperability fairly easy, allowing one to keep one’s Eurorack modules and use them with newer Kosmo modules. For that matter, there’s no necessity to switch completely and irrevocably from one to the other. One can choose to go forward buying and building both formats.

The electronic compatibility also allows one to leverage one of Eurorack’s main advantages: The availability of many, many DIY modules. On modulargrid.net there’s something like 18 times as many DIY Eurorack modules listed as the next highest format (which is Serge). Electrically, a Eurorack module is indistinguishable from a Kosmo module. It’s only the panel size and jack size that differ. It requires some work but should be very feasible to take just about any DIY Eurorack module PCB and repanel it as Kosmo. From that point of view the number of DIY Kosmo modules available at this writing isn’t 4 but 1877.

Repaneling has a down side which is, well, repaneling. Those panels aren’t going to make themselves.

LMNC says Kosmo’s panel size was “Inspired by the simplicity of finding 20 cm panels”, but 20 cm panels are not simple to find in the US. Aluminum prices here, at least for small orders of small pieces, seem to be substantially higher than in the UK. Then you have to cut the stuff, and safely cutting aluminum is not that easy. A handheld jigsaw is said to work, though getting a good straight cut would be a challenge, or a bandsaw with carbide blade. And apparently it’s possible to use a table saw, if you own a table saw.

Aluminum isn’t the only option. There’s the PCB approach; pricier, but it comes cut to size with all your holes drilled and slots cut and graphics silkscreened.

Then there’s wood. Bastl Instruments sells Eurorack modules with wood panels. Wood’s relatively cheap, environmentally friendly, easy to get, easy to cut, easy to drill, easy to paint.

But you still have to cut it, drill it, and paint it.

Another troublesome thing about repaneling is the mechanical connection of the PCB to the panel. Most Eurorack modules have at least some of the panel components mounted on the PCB, providing the physical connection. If you move all the panel components off-board in creating a larger, more ergonomic panel, then you lose that connection. You can use standoffs, but you need to find a way to make standoffs work with a board not designed for them. In some cases one can probably keep one or two panel components on-board and work the panel design around that. Some modules use a panel PCB, into which a main PCB plugs; for those you could just design a new panel PCB. Board mounting would seem to be a solvable problem, though the solutions may vary case by case.

Repaneling takes effort, but can be seen as an opportunity. Not only an opportunity to replace small knobs with larger and tight spacings with wider, but to impose your own uniform aesthetic on the synth. Rather than a hodgepodge of different makers’ choices of colors, knob styles, fonts, and so on, you can end up with something more like, say, a classic Moog modular: A whole system with a unified appearance. Does that matter? Appearance is not something I obsess over. But I do have my preferences, and appreciate an opportunity to pursue them.

It’s also an opportunity to standardize. Modules with panel components mounted on PC boards force you to use components whose footprint matches the designers’ choices. You might need six of this jack for one module, four of that jack for another, and five of another jack for a third. Moving the panel components off board — or creating your own panel PCB for them to reside on — means you can bulk buy your favorite jacks and knobs and use them everywhere.

Here’s one more benefit of switching: You’re stepping off the beaten path, and that’s liberating. You’re not subject to any majority’s expectations. The module that’s the latest must-have thing over on the Eurorack side, you can safely ignore unless you really want it. That’s true of any non-Eurorack format, but especially the fringe, DIY-only Kosmo. Building Kosmo tells the world (and yourself) you have your own, noncommercial road, and you like it that way.

Early this month my thinking was that while I appreciate the appeal, I probably wouldn’t ever switch away from Eurorack to a larger format partly because of my investment in Eurorack so far and partly because I don’t have a ton of space for a larger system. But after recent thinking about it I’ve talked myself into designing a hybrid case, with both 3U and 20 cm rows, and making my next several modules Kosmo. I can still use my investment, and as for space, I’ve just done some rearranging and the space is there, and it’s not as if I’m gigging with my synth. The downsides of there being no commercially available built modules or full kits and very few commercially available panel and PCB sets aren’t that significant. The benefits of having something more playable, more in line with my aesthetic, more uniform in design and construction, and more idiosyncratically personal are important ones.

I’ve just sent off an order to have my first Kosmo front panel made. We’ll see how this goes. If I run into problems or just don’t like what I’m getting into, I’ll get out, but I don’t think I will.

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