Custom-Unit | 3op bank FM synth

i tried to build an fm synth like the humbleaudio one, which is not released yet, but which looks very promising:

instead of 4 ops i created 3 operator. (more easy for me:-))
and i took the rows from high to bottom, not from left to right… not sure if this was the best idea, but it seemed to me more logical during i made it.
also i was more interested in the matrix mixer beeing cv controlable than in the index… also no shape for the start, but we could change this later.
in the end its not about cloning the humbleaudio one, but use it just for inspiration…

now, it works, but please see this as a work in progress, i need your help. This is nothing special, there are a lot of people much much more cappable than me in doing such things, so i just began this. And i hope you guys can teach me what i did wrong or what can be done more easy and so on.

about the synth: its a 3op synth with a matrix mixer. (No envelopes! those should be applied from the outside. like in the synth in the picture…)
3 sine synths which can PM (not FM!) each other and itself freely.

The “A” Row is about OP1.
A1 - Op1 into Op1
A2 - Op1 into Op2
A3 - Op1 into Op3

The “B” Row is about OP2.
B1 - Op2 into Op1
B2 - Op2 into Op2
B3 - Op2 into Op3

The “C” Row is about OP3.
B1 - Op3 into Op1
B2 - Op3 into Op2
B3 - Op3 into Op3

(disclaimer: “OPx into OPy” means that OPx will modulate the Phase of OPy)

The “D” Row is about the Pitch. Theres a scale quantiser after the input.
D1 - Pitch of OP1
D2 - Pitch of OP2
D3 - Pitch of OP3

thats it for starters. maybe a general tuning knob should be there.
more should be added in the future, but for now thats it.

i like how it sounds, but i have some problem with the “gain staging” of the incoming cv.
When i just PM one OP i would like to raise the gain, but if i do this for all and i PM everything i pretty quickly just get noise.
so thats the reason i put an limiter into every PM operator.
but nonetheless, i´m sure theres a better way to do this.

also, is there a way to have “ratios” instead of a scaled pitch tune, like i have?
i did not found a way…

beside all that, please enjoy:

3op-synth.lua (87.7 KB)

(its a custom unit. put it inside the “presets” - “units” - “custome-units” and load a custom unit. than open the preset there.)

all the best,


I played with this unit yesterday and enjoyed it a lot. Just patching lfo’s into the modulation points and enjoying the drone. Very interesting results! I couldn’t make out if there is something like a master V/Oct control to reliably control the pitch, but honestly I didn’t really try to use it in the classic oscillator sense either.

It does make me look forward to having more envelope power inside of the ER-301, especially exponential curves.

Thanks for the unit!

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yes, right now there is no master, just the single v/oct inputs.
the reason is that all A-D Patchpoints are used, and the “in” and “G” inputs seem to have offsets in it, so if i patch those to the v/oct in it gets strange… but maybe i made a simple mistake there and thats all…

the JAG is my best friend with such custom units. (i have some of those:-))
i just patch all the JAG ourputs to the er301 inputs and than i sit there and listen:-)

It sounds great when modulated by just friends!
Feel free to share other units :slight_smile:

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great Custom Unit, thanks a lot for sharing

are you speaking of the Wiard JAG Joystick Axis Generator ?

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Yes, the Malekko Version of it…:slight_smile:
It’s my favorite module…

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ah thanks for the reply, what are feeding you it normally, most Joystick X Y outs i think, but what other CV works good with the Module ?

I mainly feed it with my e350. I just use the e350 as an lfo. It has two outputs, and its perfect for this.
no joystick so far…