@weasel79 and I are working on a mini axo core concept based on a prototype layout I did a while ago. He's on holiday at the moment, and I'm a bit busy with another project but when we left off we were discussing doing an initial run.
I'd like your feedback on part of the idea: I'm thinking of doing a "base" mini module with minimal IO, think of Raspberry Pi Zero scale with the addition maybe a couple of 3.5mm jacks. I then want to do IO modules that can stack on top, so full size DIN and 1/4" jacks etc could be easily added. Another stacked module idea would be one with a bunch of CV IO possibly based on the MAX chip that @weasel79 has done some experiments with.
The question is exactly how much should be cut from the base module and move to expansion modules. I think the base module should be actually usable without soldering, so maybe Micro USB power/data and host like the Pi Zero, SD card and 3.5mm in and out. Should the headphone jack stay on the base or can it be cut? Another issue: I'd like the base module to be purely surface mount components, again visualize the scale of the Pi Zero for comparison.