Audio – Arduino – Awesome

June 2020 Update #1

Sooooo…. You know how things are going perfectly groovy and you are rolling out this awesome long term Synth project and then all of a sudden the entire world just goes to hell? Oh you don’t? You’re a time-traveler?! From the FUTURE?!! And you’re here to tell me that eventually 2020 sort of kind of ends and things get better and then we decide to just not count this as year and 2021 becomes the new 2020 and we just asterisk out all of this chaos from our collective memories and pretend like it all never happened?

Oh, It’s not that simple? Well then….

Pre-Pandemica 2020

First and foremost, the feedback to the first Project Volca: Kick was fantastic! I was not expecting all of the interest in watching me dissect and destroy my little friends but it must have stoked that morbid curiosity you all have! In any case it has been a blast getting to learn from and interact with all of you who sent emails or messages on Reddit, etc. You are the loveliest and I appreciate your continued interest despite my lack of output recently. I am not one who just gives up on these sort of things so hell or high water things are going to start moving again.

Before we all got a big bowl of Covid in our lives this year I rolled out Volca Kick dissection and have also completed similar tear downs for the mod points on the Volca Keys and Volca Bass. However one problem that I ran into as I was tinkering on those second two was that I now had three Volcas on the dissection table at the same time with a mess of wires and 1/8″ jacks all over the place. With my end goal of building a mega machine out of all of these it quickly became apparent that I was going to need plan my case and interface so I decided to pause my plans to publish the next two parts of series to get that done so I could actually have things properly wired up as I keep going.

Of course then our waiter arrived with our hot steamy bowl of virus soup with a side of “bummer” and “depression”. That is where things came to a very abrupt stop.

2020: The Series

I’ve been working from home for the last 4 years and my office/studio space is big enough for my desk and a workbench but when my wife also needed to join the remote workers alliance I had to do the whole “be a good husband and share” thing and decided that it would be best to move my workbench to the basement so we could cram another full size desk into my office. Downside to moving the workbench to the basement is that for the last year I’ve been slowly finishing the basement as my new studio space but things are far from done down there.

Long story short, I had to pause all of the projects I was working on. I’ve neglected posting any updates to things for a while because it has honestly felt pretty selfish to whine about things I have not been able to do while being fortunate enough to have employment that has been insanely busy and more importantly my family and I have had our health. I have been able to slowly start getting things rolling again in small capacities so it felt like the right time to actually sit down and roll out some positive news.

Face Masks and Face Panels

The last big thing I was able to eek out before moving my workspace was to design and have a friend of mine 3D print a panel for me to use as my interface for the completed project:

All of the components are loaded up in their spots and Ive been slowly working on getting it all wired together. My God did I not consider how long that was going to take… The panel will be interfaced with a raspberry pi 4 and teensy 4.0 with dual audio shields to create some effects and signal mixing. I will post some pictures of the almost complete panel in a couple of days. Its bright pink and with some addressable LEDs placed behind the panel strategically, it also diffuses the light from those for some pretty gnarly looking effects!

VolcaSample-Live update

Next, there is one other project that I had not mentioned in any previous posts (but some may already be aware that I was the one working on it) and that is the fabled Volca Sample Line-In Mod that I first teased I was working on last year in a post on the r/volcas reddit board. This thing has been… well a complete and total disaster BUT it was an educational disaster none-the-less. See when I first decided to tackle it I was just beginning to learn Python and while Python is an incredibly friendly language for newcomers and I have a background in coding ,the Korg Syros tool that is required to actually turn audio clips into samples is written in C# which is close to Python but also nothing like Python at the same time… its this whole big thing.

This project out started out as me trying to get the Syro libraries to compile for Arduino and there was no feasible way to get a high enough quality audio signal out of the arduino so I switched over to the Teensy 4.0 with an audio shield given its more robust DAC and separate ADC for recording directly to it. Its actually very easy to get a decent quality sample recorded to the teensy but the problem comes in when trying to send the Syro stream to the VS. The update will start but regardless of what different cables/volume settings I have tried nothing seems to get the update past the 50% mark before it fails.

I have poured countless hours into this beast at this point and the solution is out there, likely very close, but my Python skills are likely not to a point where I am able to debug the problem correctly. So I am turning this over to the community to see if someone else can figure out the issue where I have failed. I do at least suspect that the issue could like with the Teensy not being able to read from the SD card quickly enough to keep the Syro Stream stable enough but that is strictly a hunch. If you want to take a crack at it, I posted it on github. What you will find there are the libraries to compile on the Teensy in their pure form. I had an incredibly generous user on the Teensy forums who helped wrap the Syro libraries in a way that they could be easily used on the Teensy so I am sharing his work so that anything Ive changed or attempted to tweek are taken out of the equation. Also, I have enjoyed tackling this thing for so long I really would love to get to the bottom of it myself but also dont want to keep the community waiting when someone else will very likely be able to solve the puzzle where I have failed.

My friends are so depressed…

So that brings us to the end of this super long update… Site is getting some work today and I am continuing to work on the interface and rack for the volcas to be mounted into. I am going to hold off on posting the Volca Keys and Volca Bass teardowns until I at least get the I/O jacks wired up on the interface so I have a clean way to know where everything is connected at. I also want to get some more Oscilloscope readings to share on the posts as I think that information is very beneficial for understanding what Korgs intentions were for all of these different secret mods on the boards. I will do my best to get updates out as soon as possible but as we all know, were likely days away from an alien invasion, zombie uprising or reboot of All in the Family, any of which could cause some temporary delays again. At the very least I will do better keeping the site updated!