Hi everyone!

I've been busing sketching and scheming this little Eurorack system. I'd like to do sine-y sounds, sort of like flutes, organs, I'd like to be able to do chords and resonating tones, and I want the whole thing to sound as clear and clean as it can. I plan on doing both slow sequences of tones/chords (I'm into phasing tones and combination tones, Alvin Lucier-style) and bleepy techno. I will be sequencing from a SQ1 as it's a convenient, cheap option.

I have a few questions:

  • newbie question: if I don't plug in an external sequencer, do I need a clock? I worry about the sequencer being quite constraining on what I can do with this
  • newbie question #2: do I miss some critical part of a functional system? A mixer, maybe? A second VCA? Also, not sure about how these 3 oscs all feed into the ADSR? (hence the mult. I don't know if that's how it's done.)
  • The oscs are all sines. I picked these because they're apparently quite pure, they sound great in the videos and are not too expensive, but they might not be ideal in terms of ergonomics/fine tuning and/or functionality?
  • I've been thinking of replacing them with the Ensemble Osc from 4ms but I'm worried about it being a bit too ready to use/prescriptive. I like the idea of something more basic. Your thoughts will be apreciated.
  • Chose this ring mod that apparently sounds quite clear. It might go to make room for something else. Any suggestion?
  • I'm very much into phasing tones, combination tones, Shepards. Any idea/tip about this?
  • Also, any tips about resonating filters? A second filter? Something else?

Thanks! Take care, everyone


please mark your rack as public and post the url - fuzzy jpgs aren't that helpful to us helping you - no click through or mouse over - and with 11k+ modules available, no one knows all of them!!

but for starters:

sq-1: probably not the best sequencer for sequencing chords... only 1 note at a time... so no ability to go from a major chord to a minor chord, for example... don't just buy modules/things because they are cheap buy the modules you really want/need after extensive research and thinking about how you will actually use them in practice, otherwise you'll be swapping modules in and out until you do find the ones you want/need - which is a false economy - which leads me to...

oscillators: whilst these may seem like a great idea, I think you'll have issues with them... they are tiny and use trimmers and as such are probably not going to be great for precise tuning & having them next to each other will make them almost impossible to adjust when patched - so don't rack them next to each other! - remember that in eurorack 1hp is just 1/5" (5.08mm)...

a lot of people are shocked by how small modules are once they've actually seen them! also pay attention to module and case depth... not all modules fit in all cases - 2hp modules can be quite deep - as the pcbs are perpendicular to the panels - and can be quite fragile

whilst in general doepfer make some fantastic modules, especially their utilities and filters - their midi modules are best described as not great - if you need a midi module I'd go for something else, probably with more channels - if you want chords you'll probably want at least 4 channels - mutant brain might be a better option - & it has extra gate/trigger outputs so you can use midi clock for example, if you wish - but I'd seriously think about how you're going to sequence your modular - pick either midi or cv and then get a module that actually fulfills your needs (I don't think either of the options you've picked do!)

newbie question: if I don't plug in an external sequencer, do I need a clock? I worry about the sequencer being quite constraining on what I can do with this

it depends - do you want to have modulation etc that's in sync with the notes that are being played? the sq-1 is quite a basic sequencer... especially if you want to play chords! find one that's more advanced - preferably with enough channels to sequence all your voices independantly... I like the erica black sequencer... it has 4 channels and each channel has quantized pitch/gates/modulation, has an internal clock, each channel can run at a different division/multiplication, and a clock out for sending to other modules!

newbie question #2: do I miss some critical part of a functional system? A mixer, maybe? A second VCA? Also, not sure about how these 3 oscs all feed into the ADSR? (hence the mult. I don't know if that's how it's done.)

mixers are incredibly useful, you'll likely want a few of them - not just for audio, but also for combining modulation... same with vcas - useful for both audio and cv - again you'll probably want at least a few - I'd go for a quad cascading vca - such as a veils clone...

vco outs go to vca inputs - envelopes (ie an adsr) go to the cv inputs of the vca so they can open and close it - sounds like some further reading on the basics of modular synthesis is a good idea - the stickies at the top of the 1u & 3u subforum on modwiggler are a great place to start!!!

The oscs are all sines. I picked these because they're apparently quite pure, they sound great in the videos and are not too expensive, but they might not be ideal in terms of ergonomics/fine tuning and/or functionality?

if you replace might with WILL in the sentance above you will be correct!

buy vcos that are bigger, have proper knobs on them and not trimmers (especially for pitch - tuning!!) and preferably with more functionality - multiple waveforms are a good idea (options/verstiltiy), as are things like pwm... if you seriously want only very pure sines, you might find you are better off using resonant filters as sound sources - do more research!!!

there are plenty of good inexpensive(ish) vcos about... probably a bit more expensive than those 2hp ones, but not necessarily that much more! but you may end up wanting a simple mixer for each - so you can combine waveforms...

I've been thinking of replacing them with the Ensemble Osc from 4ms but I'm worried about it being a bit too ready to use/prescriptive. I like the idea of something more basic. Your thoughts will be apreciated.

ah the debate of 'modular synthesis' vs 'synthesis with modules'.... both are valid, as are all points in between... but to start I'd recommend more basic modules - making up a single voice and learning how to use that inside and out before adding more voices... at which point a module like the ensemble oscillator, might be a good option - make sure you understand how to sequence it properly - iirc you really want more than 1 sequencer channel - either to sequence root and chord type, or to send it multiple pitches to play at once - also I'm not convinced that it will do full polyphony - paraphony yes, but polyphony??? again do your research!

Chose this ring mod that apparently sounds quite clear. It might go to make room for something else. Any suggestion?

why a ring mod? doesn't fit with your pure/clean aesthetic... maybe a multi-function effect module would be better... fx aid pro (so you can see what you are adoing) would be my pick!

I'm very much into phasing tones, combination tones, Shepards. Any idea/tip about this?

phasing - as in the effect? get a phaser - the new doepfer one looks good
combining tones - mixer &/or cascading vca
shepard tones - I'm sure you can patch it but there's at least one module that has this built in expert sleepers general CV - which is a great and undervalued module... despite it's tiny screen!

Also, any tips about resonating filters? A second filter? Something else?

if you want polyphony rather than paraphony - you'll want a filter per oscillator (& possibly the same filter for each) - spend some time fiinding the one(s) you like... even if you only want paraphony, multiple filters will give you more choices/versatility, but they can come later...

I'd also recommend taking a look at my signature file & spending a fair amount of time thinking about what it says - the formula is a hint at (loosely) getting the most versatility from a modular synthesizer for the least expense...

I hope this has all been helpful...

"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia

Utility modules are the dull polish that makes the shiny modules actually shine!!!

sound sources < sound modifiers < modulation sources < utilities


Jim!

Thank you so much for taking the time to write this incredibly resourceful reply, and educate me on some badly overlooked basics! Truly, I've learned so many things from your message.

I've reworked a (hopefully) improved setup here:

ModularGrid Rack

(if you have the time and patience to check it out – I don't want to stretch it here.) In a nutshell (or rather, a 500€ case…):

  • there's the Mutant better MIDI input you suggested
  • just beneath it are an offset module and a Disting module (the idea is to be able to generate parrallel chords from a keyboard, which, come to think of it, is the main/only way I currently use "chords" in my practice). Disting seems nifty, but maybe something cheaper would work just as well for this application.
  • OSCs are now all resonance filters, which is a great, elegant solution, and I love it. I find I really love sines and at that point, don't care much about other waveforms in terms of timbre
  • there's the Intellijel quad cascading VCA/mixer, which should allow for a number of mixing uses?
  • then an apparently quite clear, clean multifilter
  • a basic quad LFO
  • I followed your perceptive advice and ditched the ring mod. Instead I guess I could FM the VCFs sines for instance?
  • then a MATHS module which seems to be so convenient for all sorts of operations (including VC envelope generation and many other fun things)
  • and a noise source which I suppose would come handy for all sorts of things

Your signature is truly a well of wisdom… not joking here. I think I'll post-it somewhere.

I'm still thinking about the sequencing part of operations. I guess I could either use that cheap SQ1 with the parrallel chord thing (this covers most of my uses of chords really), or plug in a keyboard. For other, more 'experimental' play, maybe just use a square wave from one of the LFOs to trig something on MATHS for instance?
Then maybe invest in a more sophisticated sequencer when I feel the need for it.

Is there anything you would think is redundant? Sorely missing?

And lastly, would you have any good personal book recommendation to go through the basics of modular synthesis?

Again, many thanks for the help you gave me. It's truly appreciated.


sines, i really like doepfer A-110-4


sines, i really like doepfer A-110-4
-- Plieuwski

What in particular do you like about them? Is it how they sound?


Jim!

Thank you so much for taking the time to write this incredibly resourceful reply, and educate me on some badly overlooked basics! Truly, I've learned so many things from your message.

NP - hopefully this will be just as educational/useful!!!

something I should have mentioned earlier - I'm not convinced that polyphony or paraphony in modular is a particularly good use case - it tends to be very expensive compared to what can be achieved with a fixed architecture synth - and I think that modular really only gets interesting if you're creating complex or unusual patches that can't be achieved with a fixed architecture synth - saying that getting a poly synth that has good sine waves may be difficult and/or expensive...

I've reworked a (hopefully) improved setup here:

I'n mot convinced it's any better or worse, just different & I'm not convinced that you did a huge amount of homework before re-posting - 2 reasons for this - the time it took and that with a little bit of googling I found out that the uVCFs might have tuning problem - due to no temperature compensation - so they are likely to drift, even after initial stabilisation... as @Plieuwski suggests doepfer a-110-4s may be the answer... and are significantly cheaper than the uVCFs... at least here in the UK you can buy an a-110-4 and a doepfer filter for about the same price as an intellijel uVCF

(if you have the time and patience to check it out – I don't want to stretch it here.) In a nutshell (or rather, a 500€ case…):

  • there's the Mutant better MIDI input you suggested

good

  • just beneath it are an offset module and a Disting module (the idea is to be able to generate parrallel chords from a keyboard, which, come to think of it, is the main/only way I currently use "chords" in my practice). Disting seems nifty, but maybe something cheaper would work just as well for this application.

can you explain your intended use of the disting, with regards to this? as a second offset/precision adder? I'm not convinced! not to say that the disting isn't a useful module...

as for the offset - I wouldn't use it like this - I would tune the 'oscillators' to the correct intervals or use precision adders and precise voltages - but I almost definitely wouldn't play chords like this (see below) - I'd use the offset for shifting modulation... but see below!

plus I'd buy a better one - by that I mean multiple channels - happy nerding 3*mia, for example...

  • OSCs are now all resonance filters, which is a great, elegant solution, and I love it. I find I really love sines and at that point, don't care much about other waveforms in terms of timbre

you might not care about other waveforms now, but that doesn't mean you won't in the future, so the option of other waveforms is a bonus... plus see above re tuning stability... I'd go for the a-110-4s after doing a little more research on the subject myself!

  • there's the Intellijel quad cascading VCA/mixer, which should allow for a number of mixing uses?

yes but you'll undoubtedly need more mixing as well as vcas - they are fundamental synthesis building blocks... (see below)

  • then an apparently quite clear, clean multifilter

so paraphony only!!! for true polyphony you need a filter per voice... (see below)

  • a basic quad LFO

I'd want something more fully featured than this... batumi, which has multiple waveshapes etc!!!

  • I followed your perceptive advice and ditched the ring mod. Instead I guess I could FM the VCFs sines for instance?

standard practice for fm is to use another vco... so I'd want at least 2 oscillators per voice... for both fm or slight de-tuning (which makes them fatter)

  • then a MATHS module which seems to be so convenient for all sorts of operations (including VC envelope generation and many other fun things)

it's a good start - especially when the 'maths illustrated supplement' is worked through multiple times - thinking what, why, how... you'll almost definitely want to duplicate most of the functionality that it offers - so that you can use maths for more complex things

  • and a noise source which I suppose would come handy for all sorts of things

yes but again massively benefits if you have more mixers - mixing a small amount of noise into a voice or modulation is a good idea - you almost definitely do not need this to start with, though...

Your signature is truly a well of wisdom… not joking here. I think I'll post-it somewhere.

yeah - I should get some posters printed and sell them

Is there anything you would think is redundant? Sorely missing?

I don't think that there's anything particularly 'redundant' although I dislike that concept in modular - something's only redundant if you don't use it - and personally I don't think there's enough here for that to happen - if you want polyphony, or even paraphony, you'll need duplicates of modules...

saying that I don't think I'd buy the offset module just yet - channels 2 & 3 of maths will cover this for now - when you get into self patching maths to do interesting things and you find yourself reaching for more modulation/offset/attenuversion/mixing/logic then it's time to add those, until then I wouldn't bother...

stuff that's missing:

a mult - you'll need a way of copying the single v/oct signal from the sq-1 to multiple destinations - you'll probably want more of these in the future - and you may find that you need buffered mults - but passive will do for now (& this may be stackcables or headphone splitter) - I'd get one of these to start with

more mixers - just like they say "you can never have too many vcas", I think you can never have too many mixers... sub-mixers (for mixing wave forms and/or oscillators), matrix mixers (more complex modulation, send/return, feedback patching etc) and end of chain mixers are all incredibly useful...

I probably said this before - but I'd also add a multi-fx like an fx aid pro - it'll give you a lot of options - reverb and delay are really useful... personally I'd want at least delay and reverb - but you may have other ways of applying these!

I'm still thinking about the sequencing part of operations. I guess I could either use that cheap SQ1 with the parrallel chord thing (this covers most of my uses of chords really), or plug in a keyboard. For other, more 'experimental' play, maybe just use a square wave from one of the LFOs to trig something on MATHS for instance?
Then maybe invest in a more sophisticated sequencer when I feel the need for it.

this is definitely 1 area to keep thinking about...

experimental:

triggering maths will cycle the waveform - which could be used as a source of cv for pitch, with the addition of a quantizer... but it will be repetitive, up/down only - you might want to mix in a tiny bit of noise to this before quantizing...

for the parallel chord:

put in place a plan for order of purchase - don't buy everything at once...

buy a case (I like the mantis), a single voice and the sq1 and as much of the utilties as you can (at a minimum a mult and the vca) and a modulation source and a dual envelope generator (adsr if that's what you want)

for that single voice I would buy 2 a-110-4s and a doepfer filter - possibly the A-106-5 SEM or one of the ladder filters...have alisten to the filters on line - it'll give you an idea - search for comparisions of doepfer filters on youtube

I'd also be realy tempted to add in a trigger/gate delay especially if you can find a voltage controlled one - this will allow you to experiment with phasing by patching a slight delay into the triggering of one of the envelopes

this will allow you to "proof of concept" a voice before commiting to buying multiples... both in using multiple vcos for a voice (for both out of phase and detuned oscillators as well as some fm/am etc) and also experiment with sending an interval (the mix of 2 differently tuned oscillators) to a filter to see if you like the results...

you may find that you don't like some aspect of the voice and can easily change something out at this point before continuing...

once you are happy with the voice you have then add a second... this maybe just another filter, or it may be a filter and a couple of vcos and a mixer and another mult for example...

at this point you could then add in the midi -> cv module an/or a more complex multi-channel sequencer - the sq-1 can always be used as a modulation source, or for transposing the other sequencer, or for sequencing another voice (bassline/lead etc)

I'd build this up one voice at a time and I'd aim for 4 voices - why 4 and not 3? so you can go past basic 3 note triads - either by adding in a bass note or by extending the chord (7ths, 9ths etc) - personally I'd probably only use parallel chords for "power" chords - root and 5th and the root duplicated either above or below - or to do things with major/minor chords - for ambiguity - but I guess this really depends on what else is going on!!

my 'end game' here (for polyphony) would be 4 identical voices, each with a pair of vcos, a simple mixer (maybe more than 1 - I like ones based on the moog cp-1 - for example AISynthsis' Harmonic Mixer), a dual envelope generator, a trigger/gate delay, a filter and at least one vca channel (probably more like 4 per voice - vco, filter, modulation etc) and some shared modulation (including a matrix mixer)

things I'd also consider adding in would be more modulation, waveshapers & lpgs (towards a more west-coast ideology), a different bank of filters, some simple effects - patching effects in at different pounts in the path rather than just the end of chain can be intersting!

And lastly, would you have any good personal book recommendation to go through the basics of modular synthesis?

there's patch and tweak which is an actual book... it's good but in lots of ways it's a coffee table picture book...

the stickies at the top of the 1u&3u subforum on modwiggler are good...

for more advanced synthesis techniques the sound on sound magazine 'synth secrets' series - available online for free is dificult to beat.. but is very 'east coast' centric iirc - ie this is how you mimic this instrument with a synth - which I'm not that big a fan of tbh - but I did get at leasat half way through the series - iirc there's 50+ articles - when I read it...

there are also a number of threads about more advanced books both on synthesis in genersl and modular synthesis in particular (Allen Strange, Pelsea and X without Y, for example) in the 1u & 3u and modular synthesis general discussion subforums of modwiggler

again - hope this helps!! good luck - more questions? keep them coming...

"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia

Utility modules are the dull polish that makes the shiny modules actually shine!!!

sound sources < sound modifiers < modulation sources < utilities


I'm building my first Eurorack system as well, after some expience with semi-modular synths and VCV rack etc.

I was personally looking at the Fully Wired Electronics Transistor Ladder Filter https://www.modulargrid.net/e/fully-wired-electronics-transistor-ladder-filter. I could be making the completely wrong choice but I quite like the sound of it, with it being a ladder filter and all. Plus (Again I could be completely wrong) but it doesnt seem overly expenisive if I don't like it in the end. From what I've seen I assume it self-oscillates.


I'm building my first Eurorack system as well, after some expience with semi-modular synths and VCV rack etc.

I was personally looking at the Fully Wired Electronics Transistor Ladder Filter https://www.modulargrid.net/e/fully-wired-electronics-transistor-ladder-filter. I could be making the completely wrong choice but I quite like the sound of it, with it being a ladder filter and all. Plus (Again I could be completely wrong) but it doesnt seem overly expenisive if I don't like it in the end. From what I've seen I assume it self-oscillates.
-- timeandspace

seems inexpensive - this in itself is not a good reason to buy it though... that you like the sound of it is, though!

the description states that it tracks v/oct - which might indicate that it self resonates. or might just mean that the cut-off frequency is calibrated to v/oct... I'd contact the manufacturer for clarification before buying, if I were you, if this is important to you

"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia

Utility modules are the dull polish that makes the shiny modules actually shine!!!

sound sources < sound modifiers < modulation sources < utilities