Mutable Instruments Marbles - Secret Modes and Calibration - DIY Clone

[@jamesde7775]

Hello, great video. I just finished my build but have a few questions. I did Antumbra's Cara. Am i correct in thinking that i need to play the audio file in from the MI website first and then do the measurements? Also wondering how you connect your cable to your multimeter?

[@TOILmodular]

Hi. Concerning your programming question. I guess you can use the available wav file to do the initial programming and to perform the DAC offset measurements. But I cannot tell you how to create another wav file with the adjusted code containing the new DAC data points from your calibration measurements. I only know how to create a hex file, as described in my GitHub repository (link in the video description). Concerning how to connect the module to a multimeter: you have to put in a patch cable to the x or y output of the channel to be measured. Then connect the red multimeter probe to the patch cable tip and the black probe to the patch cable sleeve (ground). Easiest way is to use crocodile clips at the multimeter.

[@NikolaosTsarmpopoulos]

Thanks for sharing the video. I built the module and compiled the firmware. I'm now looking into calibrating it. My UNI-T UT50A multimeter is only 2000 counts and I wonder if it's good enough in practice. What's the difference -in practice- between an un-calibrated Marbles module and a calibrated one?

[@TOILmodular]

The calibration is needed for the internal quantizer. So without that you might not get accurate CV outputs, when using the scales of the module. I do not know how accurate you can get with the 2000 counts. But it is definitely worth a try. If it sounds good enough, it is good enough, I would say.

[@Rinzler4DP]

Those oscillators sound really good! what are you using?

[@TOILmodular]

The high pitch voice is done with my rebuild of the Kassutronics VCO. I showed it in the 1st video of my "Finding modules" playlist. The sound is done with 2 of those VCOs via FM. I shared that technique also in my "Bells" video. The 2 lower voices are from 2 Plaits clones. Unfortunately, I did not take notes about which models I used for the sound. I just played around with them, after I built them.

[@observanus]

Great walkthrough! I need to calibrate my factory Marbles (quantized CV is flat) and tried to calibrate and compile into a Wav file since I don't have a programmer but it does not work. Do you know if it's possible to offset the DAC via a .wav firmware or do I need a programmer? Thanks a bunch!

[@TOILmodular]

I have not tried that myself. But I am pretty sure that you can do that, if you can create a WAV file from the code adjusted with the calibration values. At least the MI documentation describes the procedure of uploading the firmware via an audio file.

[@observanus]

@@TOILmodular Cool, I’ll give it a few more goes. Thanks a bunch, appreciate it!

[@badador]

thanks for the instructions. I’m just a bit unclear about this. so we should program the mcu with .hex file first, then measure the calibration and finally recompile the hex file with those measurements and program the mcu again with the new hex file? did I get that right?

[@TOILmodular]

Yes, that’s correct. As far as I understand, each DAC is slightly different. The 1st programming with the original code is used as a basis to get data about the DAC setting. The measurements then determine the required offset for each channel. So the code can be adjusted. The 2nd programming with the adjustments then takes into account those specifics for the used DAC. I hope, that helps you to get some better understanding of the process and the purpose behind it.

[@badador]

@@TOILmodular thank you so much, it is clear now 🙏🏻

[@btAC242]

Hello! can you explain what is local ARM folder in your "Compiling Procedure for Mutable Instruments Eurorack Module Firmware", what is ARM/stmlib? there is no stmlib folder in ARM from this repository...

[@TOILmodular]

Thanks for the feedback. You are right, that step 3 was not described correctly. You actually find that folder Stalin in the downloaded code from MI (step 1), not the one from my repository. My mistake, I adjusted the text in step 3. Let me know, if it is still unclear.

[@btAC242]

Thanks. guess i do everything right and have this: stmlib/makefile.inc:373: build/marbles_bootloader/depends.mk: No such file or directory @@TOILmodular

[@TOILmodular]

I fear, I do not quite understand. What process step are you at, and what problem do you face? You can send me an email to share more details.

[@maerisrael]

Hi I was wondering if you have Gerber files for front panels for your designs? I'd like to build a few of them but I'm unclear how to get the panels fabricated. Thanks for publishing through hole designs for the MI modules...

[@TOILmodular]

Thanks for your feedback. Honestly saying, I was thinking about that at the beginning. I did not want to do it, since I do not follow the HP standard for the width. I use sliding nuts. On the other hand, I already got that request a few times. So I started thinking about providing panel Gerbers. Cannot promise yet though. I will let you know.

[@maerisrael]

​@TOILmodular maybe using oblong pill-shaped mounting holes would accommodate nonstandard hp width for either sliding nuts or fixed width inserts. Check out the Antumbra 6Mix front panel, for instance. Would love to build several of your designs (plaits, clouds, and tides) if I can also get the panels fabricated!

[@TOILmodular]

Thanks for the advice. I have to admit, I am not a fan of those holes, as they are a pain in the… when using sliding nuts. But it is not just the mounting holes. I also have to adjust the module width to avoid gaps between modules. I also have to think about pot hole diameters, etc. I am currently thinking about it. Not yet decided.