@Aria_Salvatrice indeed, that’s my goal 
@bpaturzo It would be great to see VCV-Rack in OS, but unfortunately that’s too hard for me to do. I’ll take a closer look at the DACs, thank you.
Oh it’s too much for me too – just thinking out loud. It would be more in Andrew’s line. But just think of it – VCV would be an intelligent router with the modules operating autonomously. Windows has too much bloat and overhead to host VCV. That’s why I’m excited and plan on doing the Sonaremin project – thanks for bringing that up, as I didn’t know about it. Also, you might check out what they are doing with the Axoloti project – the core module runs Pure Data / MAX type s/w modules on a little board with midi in/out and audio out.
@bpaturzo I found something interesting, besides a lot of sound manipulation, this guy explains how to make a MIDI -> DAC system, with a Teensy (which is just an Arduino on steroids) the code being already done the hardest part of the work is done, and the hardware part is really very simple.
But other questions come to my mind, how many channels does it control?
And also I would have liked to know the average amperage of a CV line to know if I can do my project without any power supply other than the Raspberry’s one (which would already power the Arduino via USB).
More generally, I’m currently looking for resources on CVs, to know if there are standards etc…
I was yesterday at a modular and machines jam, I was able to make some contacts; a guy told me that for the notes the CV standard was from -5v to +5v but he wasn’t 100% sure. He also accepted that I test the compatibility of my modules with his
You should really spend a huge amount of time with this module:
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@stoermelder The problem with scope is that you can only read the voltage sent, and I need to know if the modules transform this voltage into a standard value. Let me put it this way: it’s all possible to send from -12v to +12v in a v/oct input, but nothing tells us that internally the module doesn’t transform this signal on another scale (it’s not measurable with scope in VCV). And it’s standards after treatment that I need.
Also Scope doesn’t let me know the amperage, only the voltage.
It’s very kind of you to help me, but could you please be less condescending?
No problem, I won’t comment anymore. You should definitively talk to Leonardo from Vult about how hard it is designing a hardware module.
Voltage in Vcv usually goes from -10v to 10v.
Why would you need to know that ? in CV/Gate only the voltage is relevant.
And please don’t call out people as condescending when they are just trying to help you. I don’t see anything condescending about Ben’s comment.
It’s seems you are a beginner( which is totally okay), and we always advise beginners to spend time with oscilloscopes to understand what’s going on.
AFAIK Eurorack is not a DIN/ISO/IEEE/AES/EBU standard (yet), but its foundation is the Doepfer A100 system.
If you want to integrate in the eurorack world, here’s a place to start: http://www.doepfer.de/DIY/a100_diy.htm
and the doepfer A-110 schematic: http://www.doepfer.de/a110_tec.htm
Voltage in VCV modules does whatever it damn well wants, it’s not bound by the law of physics, there’s a few modules that will happily deliver 10000000 Volts if you ask nicely. But most well behaved ones follow the standards of keeping it to a range of 10V peak to peak.
It is possible to make a module using the Raspberry Pi and a custom controller, but there are some caveats.
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Cost: It would be cheaper to build for yourself but probably not to sell. For a product, in order to reduce production cost it’s better to have everything as integrated as possible. It could make sense if sold as DIY kit and you don’t have to manufacture anything.
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Power: I haven’t measure the power consumption of a Raspberry Pi zero, but I imagine that it’s going to be much higher than a microcontroller. The Freak module consumes a maximum of 100mA, which is not too high but neither too low. I have other module that consumes 500mA. I tend to not use it because my power supply is 2A max and using that one cuts 1/4 of the power that can be used by ~15 analog modules.
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Reliability: I have a bunch of Raspberry Pi boards (all generations) running different things at home. Some have been running for years without powering down. But other have been more problematic, specially on the SD card side, which needs to have a safe shutdown mode. In my real eurorack I just turn the power off and everything is fine. You’ll have to develop some hardware/software mechanism to make sure that the device will handle the power down without anything being corrupted.
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Boot time: Personally I hate boot time. All the modules I have are ready to use in less than a second after I power the rack. I know that it’s possible to reduce the boot time, but I don’t think it can be as good as a microcontroller.
Having said that, I actually have a Raspberry Pi running Vult Incubus, but it does not use any VCV Rack code. I took the DSP code and wrapped it into a custom executable. It works fine, but I have all the issues I mentioned above. It’s a cool experiment though.
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