Experimenting with 84hp

I'm considering getting into Eurorack and I've been experimenting with laying out a rack to see if I could put something together that would be worthwhile. I have the constraint that this rig must fit in 3U of a 19" rack, so I'm limited to the 84hp that will fit in a TipTop Happy Ending kit. I'd like to use it for dreamy ambient and shoegaze. I'd like the rig to include an analog oscillator and an analog filter. I'd like to both play from a midi controller and have a generative module. I'd like to be able to layer a couple of voices.

That's a tall order for only 84hp, but part of the fun for me is to try to build something usable that fits that tight constraint. I realize that there are a lot of tiny knobs in my future :-).

Here's what I have so far.

With my tight constraints, the FH2 for midi input is useful because it can do double duty, supplying envelopes and LFOs in addition to converting from midi. I expect to use midi CC for some modulation, so I'll be getting CV for those from the FH2. TS-L is appealing due to the variety of controllable parameters. The 2hp VCO will be useful for a second voice or for FM to the TS-L (or vice versa). Nanorings rounds out the tone generation section. The knobs on the 2hp VCA seem useful for helping balance the levels of the tone generators.

Ochd and uPeaks are there for modulation and Pachinko for sequencing. For effects, I have uBurst, Doupples, and Milky Way. The filter frequency knob is the one knob that must be a decent size in this rig. Disting EX is there as a wild card to fill in for anything I might need in a patch, for example logical utilities. Con is useful since it has input as well as output, so I could feed line level input to this rig for effects processing.

Any feedback would be appreciated. I understand this is generally considered too small a rig to be useful, but I'm willing to scale back my expectations in order to get something that fits in 84hp.

EDITED Sep 8th 2021, 22:52

why the constraint on size? masochism?

these maybe the modules you want but you do not have the modules you need to get the modules you want to play together nicely

you are trying to do too much in too small a space and you will probably have an unpleasant playing experience

there are at least 5 potential voices there - and no mixing - so it won't work as you expect anyway - in fact it just won't work

throw it away and strip back your requirements to the bare minimum and start again - preferably in a bigger case (Mantis is good and reasonably priced as is the lc9) so that you may actually enjoy playing your instrument

It is asking a lot to just be starting in modular AND to design a solid small build.

My best suggestion is to look up forum user Lugia (who is super good at rack design) and review several of his small to medium racks. Notice the balance of modules: approximate % of things that make sound, % of things that make control signal, % of other stuff that a modular needs to run. Notice the “must have” items which appear in most racks. As Jim said, there’s a base complement of utilities that are a must for most stand alone rigs. If you seriously study 5-10 of those racks it will answer a ton of your questions and put you in a better position to get a good initial plan.

That said, there’s maybe no substitute to getting in the game, making a few mistakes, and learning by trial and error what will suit you. That also argues for a bigger case; so you have room to experiment and grow. If you can afford it, two cases would be good. A tiny one to suit your small footprint goals, and a bigger one to give you some room to experiment. Or in software using VCVrack to try some of your ideas, that can help too.

Good luck!

To me, that all looks a bit cramped and (I'm not sure why) a bit ugly. I wouldn't enjoy playing with it. Could you get a rack that is powered? You could do without the power supply then and gain a few more hp? Just my two cents... best of luck with it all.

A rackmount case that doesn't require 4hp for power sounds interesting, do you have a link?

I have indeed studied the small racks suggested by Lugia. His feedback posts are a wonderful resource here and I discovered several of the modules in my proposed rack from his suggestions. I suspect I will be doing some iterative experiments with this, for example my idea of using the input attenuators on the VCAs as a mixer is something I'll have to try out to see if it meets my needs.

A rackmount case that doesn't require 4hp for power sounds interesting, do you have a link?

I have indeed studied the small racks suggested by Lugia. His feedback posts are a wonderful resource here and I discovered several of the modules in my proposed rack from his suggestions. I suspect I will be doing some iterative experiments with this, for example my idea of using the input attenuators on the VCAs as a mixer is something I'll have to try out to see if it meets my needs.

-- asleepwheel

Hi, I have the Nifty Case. I quite like it. 84hp with power, two channels of midi to CV, plus a clock and the case itself is quite nicely built. As everyone says, though, you will probably very soon wish you'd bought a bigger case - although I do quite like having a small case personally. It fits on my desk nicely. But I filled it with some not quite so small modules. Here are my choices:

Correct me if I'm wrong, but the Nifty case isn't rackmountable, nor is it 3U. Or is there another version?

I like your module choices, especially the LxD and RND, thanks! I think you're right, I should be aiming for fewer, but larger, modules.

Correct me if I'm wrong, but the Nifty case isn't rackmountable, nor is it 3U. Or is there another version?

I like your module choices, especially the LxD and RND, thanks! I think you're right, I should be aiming for fewer, but larger, modules.
-- asleepwheel

Hi, sorry, I didn't pick up that you wanted it rack-mountable. My bad :). Yep, I love the LxD - it sounds nice to my ears and has two different flavours in 4hp. The RND is very useful too, for such a tiny module.

Here's the rig that I ended up actually building:

Here's a track I created with it:

Thoughts so far:

I wanted something that I could use to do ambient generative music as well as be controlled from midi, and also have a line in so I can use it for effects, and I succeeded on that score. I have an analog audio path from VCO to VCF when I want strictly analog.

As I mentioned above, with the constraints I have, I knew I'd be in for some cramped controls, but I put a premium on getting decent-sized knobs for the controls I'd be riding the most. My soundsources go into the 3xVCA so I use it for mixing as well as applying amplitude modulation, so those knobs are are important, and I'm happy with that module. The knobs on Disting work great for me and I'll be using those a lot. The frequency knob on C4rbn is borderline adequately sized. All the little knobs are fine...either I don't access them often or precision isn't required for them. One thing I'm finding valuable is cables with an attenuator in them. That way I don't have to waste valuable hp space on simple CV attenuation.

Stages is a gem. I can use it as any combination of: quantized pitch controller, LFOs, envelopes, sequencer, slew limiter, etc.. With a small rig like this, every module must be able to do multiple jobs and Stages is priceless, especially with the qiemem firmware.

I have a little space left. I'm thinking Ochd would help me with all the slow unsynced LFOs I need for subtle movement and would free up Stages segments to be used for other tasks. I could use another tone generator, but Disting might be useful for that, in which case I'd need something to do effects processing I'm currently doing with Disting. A utility module would be handy for creative signal mangling. Any suggestions?

any suggestions:

get another row??
take a look at thonk.co.uk - they have trimmer knob covers that make them a little bit bigger and easier to use
a matrix mixer would be useful as would 3*MIA and kinks or a wmd/ssf toolbox
fx aid xl... so you get the modulation inputs and knobs that are accessible

I really like the track! Nice and dreamy and drifty. Thanks for sharing it.

Lessee...10 hp left, and you're thinking LFOs. So, how about THIS: https://www.modulargrid.net/e/beast-tek-double-dragon

Basically, it's a complex oscillator but only works in the LFO range. LFO1 can be used to crossmodulate LFO2, plenty of adjustment parameters, and some wild results.

One other point...quite important, actually...get the level converter away from the power supply. Power supplies can induce crud on audio modules that are located in close proximity; it's MUCH better to co-locate them with modules that have no audio capabilities.

Good point, thanks for the tip!

Hi Asleepwheel,

Doepfer has a rackmount case (A-100 G6) that doesn't require any power HP consuming module ;-) Kind regards, Garfield.

Thanks! It would be nice to not spend valuable hp on power. Unfortunately, I don't have room for 6U in my rack. My eurorack rig is just a small side project in an already full studio.

hahahaha
just you wait

:-)

My eurorack rig is just a small side project in an already full studio.
-- asleepwheel

You're obviously confused. Electronic music studios aren't considered "full" until you start eyeballing the ceiling as yet another "surface" for adding gear.

I'm about to start screwing cases to the wall! so 1/2 way there I suppose...