jsilence

in the background pattern

Midi controlled portable mixer

I am contemplating a project idea that is not yet full scoped and well thought out. Trying to collect my thoughts here to carve it out a little more.

Recently I have been picking up my old small synths that I never really used much, including the fabulous Axoloti, added a couple of Pocket Operators, A Novation Circuit, a Bastl Kastl and also a Koma Elektronik RH301 for syncing the clocks. Two friends of mine are also into making music so we started meeting and jamming just for fun.

This collection of smaller devices needs a mixer of course. The knobs of the older Behringer Xenyx Q1002USB I own are starting to gristle and scratch and also this part of my gear somehow does not really feel right for my setup. It is somehow doing too much while also doing too little. Hard to express my feeling towards this piece. Lets just say I don't love it any more.

Scavenging for small audio mixers I came across three interesting pieces of gear, Bastls Dude, Syntherjacks 4sum and Koma Elektroniks' Field Kit. The latter sports a nice little 4 channel mixer and a whole bunch of other lovely features, so it was added to my setup recently. But offering all the tinkering cables and mics and stuff, it still is not going to be enough mixing capability.

The remaining two mixers somehow do not offer what I am looking for. Flirting with ping-pong delays I would like the mixer be stereo. 3.5mm jacks would be prefered, since the POs and most of the other gear is on that jack format. I'm not 100% decided with mono vs stereo yet, since the synths are mostly mono as well. Maybe a combination of both? Switchable? Dunno.

The main feature I would like to have would be midi capability. I'd love to have some mixing presets and recall them with Midi program change messages. Also allowing Midi CC to control the output volumes could turn this into a musical component of the setup. I'm thinking about gating a melody playing channel with a Midi clock synced square wave to make for some interesting patterns as can be heard in some of Four Tets pieces.

The one mixer that really looks awesome with this regard is the Keith MCMillen K-Mix. But unfortunately this is out of my allocated budget range, aka 'too expensive for me'.

Looking at the excellent documentation of Syntherjacks 4sum I thought that building a device to my own specs should be doable. A challenge no doubt, but not an impossible mission. There is an ongoing discussion on crowdsourcing the design of a minimal mixer but I have the impression due to too many diverging requirements this thread is not going to be productive too soon and probably not arriving at a design that meets my requirements. Still worth skimming the discussion, since there are going to be information nuggets in there for sure.

Doubling the design of the 4mix for Stereo as a first step should not be too hard. The Potis would have to be operated by Midi though. I like endless encoders and thinking about nice rotary encoders with LEDs really got my imagination going. For Midi connectivity the mixer would need a microcontroller. The Teensy seems to be quite capable and popular for audio applications. There is an audio shield available, but this would not be enough for making a mixer, since it is lacking audio inputs. There is another interesting PCB, but I have no idea whether this board would be suitabe for the intended purpose. Maybe have to get in touch with the mentioned community.

I guess the next step would be to order double the BOM of the 4sum and to build it on a breadboard in stereo. Have to understand the amplification section that incudes the TL072 IC since I guess this would be a part that could be controlled with the GPIOs of the microcontroller.

Ordering a teensy and an audio board, some TRS Jacks for Midi in and out as well as some nice encoders and starting to tinker with the controller section would the following step.

This is a side project slowly condensing. Don't expect too much activity too soon. Feedback and input is very welcome and if you would like to join in, design and build this together with me, I'd be delighted. Open Hardware of course.

Going full Regolith (Part one)

Just a couple of days ago I reinstalled my trusty gen5 X1 Carbon Thinkpad with a fresh new 2Gb SSD using Ubuntu 20.04 on ZFS and putting Regolith on top. I had been running on Ubuntu 18.04 LTS, and back then I initially thought I'd go light and started off with Xubuntu. Then added the regular Ubuntu desktop, only to at some point lukesmithionize and dive into i3. I have been tinkering a lot, trying to converge to my own personal minimalistic setup that not only made me productive, but also looked slick and cool.

For filemanagers I tried to get in love with ranger, but somehow it did not click. Also not getting as productive as I expected in Emacs dired and a couple of other candidates like lf, nnn and broot. One point about all these console filemanagers is that they lean heavy on vi, and I am a Emacs person. So I ended up with a mixed use of Thunar and whatever I had on the console at that moment. What I missed the most was quick and easy previews of files, especially previewing image files. Yes, sxiv and feh and ranger with images in the terminal, which by the way never works half the time. Nautilus seemed bland and uncapable. Only now I am beginning to understand that a lot of its functionality is simply hidden from the user. Why hide features from the user? I don't get it. Minimalistic moronism.

On the shell I settled for zsh and gradually built up config bits and pieces like a shell collector on the sunny beach that was my browser. Oftentimes I had little idea what I was copy-pasting, simply being happy when I got it to work before I got bored or distracted. Also today I am unsure which of the roundabout twenty zsh frameworks would be the most sensible choice. Antigen seems to be broken on 20.04, at least it is throwing an error for me when I install it via apt and try to use it in my config. So is Zplug the plugin manager to use now? Brodie Robertson suggests that zsh plugin managers are only sourcing the plugin code anyway, so that they provide little benefit.

The terminal of choice was the lukesmithian flavor of the suckless terminal st. Part of the 'following luke' thing was the lazyness to patch my own config as his selection of patches seemed sensible. The only thing I did was change the cursor type to a vertical pipe.

Apart from the cruft in the filesystem I also collected a plethora of other automatically and manually installed things that I did not know and care how to get rid of, like for example virtual interfaces for docker, Virtualbox and LXC. Same goes for a bunch of PPAs that did not survive the gnaw of time and deteriorated with system upgrades. apt screamed out loud on each update like a wounded dog. But hey, somehow it limped along.

So over time I had built an environment that would work for me quite nicely, but apart from being a mess, there were a couple of things I simply could not get right. One of those was the configuration of the touchpad. I managed to get rid of the right border scrolling and the middle of the touchpad 3rd mouse button simulation. But two finger scrolling, palm detection and general sensitivity were always sub par. The touchpad under Linux is already sub par per sé, at least compared to the excellent touch pad experience of the Apple devices. I'll bitch as much as you do about Apple for numerous reasons, I know, I have been there, and have left Apple for Linux, but there are couple of things they get just right, and the touchpad is one of them.

One of the other things was the half baked mixed DE and terminal approach to file managing, manual dual monitor handling with arandr, abysmal bluetooth managing with the bt control app of whatever DE it came from and messing with Pulse Audio Control to get my audiodevices configured. Also blindly git versioning the complete dot config directory worked just as bad as sporadically symlinking and git versioning some dotfiles by hand. Did I mention the mess? Have not even talked about my botched Spacemacs/offlineimap/mu4e mail setup.

I was also constantly running out of space, so when I resolved to order a much larger SSD for the laptop I planned on setting up a new system from scratch along the way.

Read more in the next part of the story.