TS-1 is a digital synthesizer based on a Teensy 3.2. In the original, it is created with a multiplexer that queries the 15 analogue potentiometers. A Teensy 3.2 has 20 analogue connections and I asked myself why a multiplexer is needed. It is not needed. So I adapted the code a bit and changed some unpleasantness. I am a software developer and such things are particularly noticeable. Without a multiplexer, it is easier to query the individual potentiometers in an array with a structure.
Here is the modified Circuit to this
I have also created a board with ExpressPCB PCB, and here again as PDF.
I use a TEKO 363 housing and have the Frontplatte, with the free Frontplatten Designer created by Schaeffer. Here is the front panel as a PDF file Front.pdf.
Finally, the INO file with the sketch.