#6

The schematic/diagram I’ve been going from is here: https://www.cgs.synth.net/modules/cgsrr.html - hopefully that’s everything you’d need. I’m a complete beginner!

How much do you imagine these boards would go for?

#7

Thanks, looks cool! Germanium diodes can be a pain to get hold of (and vary quite a lot), but from the look of it there are silicon alternatives that will do the job.

The boards will be whatever OSH park charges; you would just order directly through them.

From their website ‘Pricing. $5 per square inch, which includes three copies of your design. For example, a 2 square inch board would cost $10 and you’d get three copies of your board. You can order as many copies as you want, as long as they’re in multiples of three’

OSH park also allows you to share a design, which can then be ordered by anyone through their website. They then collate a load of other orders together and place this (huge) order directly with the manufacturer (therefore getting the cost down for everyone).

They are a great company to get prototype PCB’s from (you’ve probably already seen their Purple PCB’s all over the place :grinning:)

#8

I love the concept. At the moment I have a few passive modules in a cardboard box but this is obviously more elegant.

The one input I have, is to normal the attenuator outputs in pais of two. So you have a simple mixer which can come in handy I guess.

1 Like
#9

Nice! I have all the components for the ring mod - been working it out on a breadboard. Only thing that would potentially be an issue is the transformers, since they’re quite big! I don’t know if that would be a problem in terms of getting it in the enclosure, but worth a go I guess :smiley:

#10

Neato! I diyed similar a good while back. I also squeezed a passive ring mid in there.

image
62C08D61-A5A6-40D0-8DE1-329CDAEE9ACA.jpeg620×627 406 KB

passive utility box, jacks in rows of 3, front to back:

  • 3 way mult
  • 3 way mult
  • ring mod
  • passive attenuator
  • passive attenuator
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#11

Grow this just a little and add the Nearness functionality to the top row and (kisses fingers).

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#12

That wouldn’t be passive anymore then…

#13

I agree; as soon as you add Eurorack power requirements (+/-12VDC supply) the best (not to mention most cost effective) place to put them is in the rack really. I’ve seen the Nearness module thread and think that it will make a neat little 2hp unit :sunglasses:

For the passive side, adding a half wave rectifier (which could replace the manual gate/switch), ring mod, and normalizing the attenuator outputs together to make a passive mixer all sound like a good idea.

I’m going to integrate those and go from there.

Thanks for the input guys!

1 Like
#14

OK, somewhat passive.

#15

Reminded me of this passive mult box I saw on instagram the other day, thought it was cool! Some touch control could be an interesting addition

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#16

This looks great! Tremendous work. :grinning:

Edit: excuse my ignorance @Ithacus, is this a single PCB? Or several teeny ones?

#17

Yep it’s several teeny ones :grinning:

Theory is they could be combined and used as people see fit :sunglasses:

Changes I’m going to make:

  • Change 5 way mult’s to 3 way (both sets normalled together).
  • Changing mult’s allows for 1/2 wave rectifier at top of enclosure (as suggested by @wednesdayayay)
  • Arrange attenuator outputs to be summed and used as passive mixer (as suggested by @boboter).

Changing anything else would mean changing the layout I currently have (I like the symmetry and overall layout as it is).

Looking at how it will work out, an individual order from OSH park for everything will leave me 1xMult, 2xRectifier, 1xLPG, 1xAttenuator and 2Manual Gate boards unused. I’ll probably do another 1590BB layout using those boards (so one OSH park order makes the 2 units).

Thanks to everyone for all the feedback so far… this forum is ace :+1:

6 Likes
#18

I like that idea. And keeping the passive stuff separate is a really handy idea.

#19

i love that the boards are teeny individuals
i would be interested in getting some built up for sure

#20

Awesome passive box! I’ve been DIY’ing some passive modules for my Bug system using the blank panels. So far I’ve made a couple of format jumblers and some switchable diode negative voltage removers (allows for logic OR function by stacking the banana outs). i’m going to do DC offset removal via switchable capacitors next to get variable decay envelopes from squarewaves/gates, some touchplates for skin patching and passive attenuators.

1 Like
#21

Edit: removed as misread/misunderstood previous message!

#22

Sorry I did edit my message too from it’s initial state!

I love your passive box design I think these types of utilities are criminally unavailable, especially for the tabletop synth/noisemaker musician.

#23

I will flag that OSH are not the cheapest option, but they are excellent quality and have good tooling. (When I say ‘not the cheapest option’ - three boards for the 16n thing we’re building work out around $250 with OSH, and I can get five for $50 from my preferred decent-quality Chinese supplier.)

Of course, your attitudes towards eg shipping, air fuel, etc, may - and should - inform your PCB supplier.

1 Like
#24

I very much like that it’s lots of small separate boards - if only to make it a plug/play toolbox of components!

#25

Yes I agree on OSH park costs, but I don’t know of an easier way to make boards easily available for anyone to order.

I can also upload the eagle files so people can have them made by their fab of choice.

Last night I revised all the modules to be under 19mm in width (max). That way people could also fit them on a 4hp panel if rack mounting is preferable (plus gives another use for any spare boards left over).

Thanks for all the positive comments so far :slightly_smiling_face: