Help me adapt this scheme for synth use

[vladosh]

I like browsing thru various Chaos Generators circuits that can be found online and there are so many , the article i share also has little pointers as to where you can replace resistors with pots ,and shares the findings in waveform according to resistance so one can just place the correct potentiometar in the right place ,however this is mostly curiosity ,i wonder if this can be adapted for synth use , i like chaos generators and i see also AD633 is available a ali ,check the full article for parts values and very in depth look at this circuit

Chaotic and Hyperchaotic Self-Oscillations of Lambda Diode

Article by Jiri Petrzela

link : https://www.mdpi.com/2076-3417/11/8/3326/htm

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[analogmonster]

I don't understand the circuit, but in principle:

- each resistor can be replaced by a pot
- if it should be voltage controlled, use a vactrol instead of a pot
- the result to be output should be buffered by a voltage follower and an 1k resistor, eventually level shifted and amplified to +/- 5V or whatever you need in your modular.

[vladosh]

thanks for reply ,this is best done all on breadboard ,but i don't have that habit yet ..too bad ...

[analogmonster]

?

What do you mean?

[vladosh]

what i meant is in order to adapt this for synth use it's best to use breadboard to test various values or if some of the opamps can take well external cv in order to synch .let's say similar to the Jerk module by non linear circuits ,or modify it to change freq besides waveform and so on . ,this exact article is very well written and also points out the resistors that can vary in order to change the way of the oscillations , it also mentions that further variables exist but were not documented ,i see it as one fun LFO or something along that line , but what i really like is that there is true experiment and invention instead of boring optimizations and buffering all over the place ,it's one thing that synth world is missing as i would like to believe there is lot of yet to be discovered even without the digital extension ,i don't work much on breadboard , i have one but i almost never use it ,as i always hurry to build whatever is next module and play with the synth
anyways here's another chaos circuit that i found this one at first glance appears can take external cv to drive it it is 2 x AD633 ,LM311 ,and Opamps
http://wesleythio.com/thio13.pdf ,the article is called - A Chaotic Circuit for Producing Gaussian Random Numbers

[vladosh]

here's another circuit that is at least cheaper to make and fail with ,i had this in my computer for ages but only now i see it again ,it's only opamps ,guess 074 can do ,it already has 5 controls but how does cycles i can only guess

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[analogmonster]

Perhaps LTSpice can help. I use this always to analyze circuits, to make them run before heating the soldering iron, after replacing vintage- or hard-to-get components by actual ones in the circuit, and testing additional voltage control or modulation capabilities before building the circuits in real life. Since I use this, most of my first shot prototype boards run as desired and can be integrated in my modular equipment immediately and without any further changes.

I don't know the capabilities of multidimensional graphs though.

[vladosh]

yeah LTSpice or a simulator of that kind is great! I downloaded few times but never played with it enough to know it well ,anyway i already have a bunch of pcb's that i need to solder .. so i don't think i'll have more time for this