Parts List:

Here are all the parts I purchased to build the Pi Looper. I'm linking to Adafruit and Sparkfun but feel free to shop around. There are shortages on the Raspberry Pi 3 B+ and Teensy 3.6 making these items difficult to find.

1 - Raspberry Pi 3 - Model B+ https://www.adafruit.com/product/3775

*UPDATE*

I installed the software onto a Raspberry Pi 4 2gb so that is now an option.

1 - Teensy 3.6 Teensy 3.6 without headers : ID 3266 : $29.95 : Adafruit Industries, Unique & fun DIY electronics and kits

26 (comes in packs of 5) - NeoPixel Mini Button PCB NeoPixel Mini Button PCB - Pack of 5 : ID 1612 : $4.95 : Adafruit Industries, Unique & fun DIY electronics and kits

1 - Nintendo DS Touch Screen https://a.co/d/0oczQ9t

1 - Adafruit Touch Screen Breakout Board https://www.adafruit.com/product/334

Below is the first touch screen I tried to use on this build but had too many issues.

1 - I can't recommend the Adafruit resistive touch screen. Otem Rellik links to a smaller Nintendo DS screen that has been retired from Sparkfun. I found this screen at Adafruit. It is bigger so it requires a bit more cutting on the 3d printed top. Resistive Touch screen - 3.7 Diagonal : ID 333 : $5.95 : Adafruit Industries, Unique & fun DIY electronics and kits

1 - Touch Screen Breakout Board Adafruit Touch Screen Breakout Board for 4 pin 1.0mm FPC : ID 3575 : $2.50 : Adafruit Industries, Unique & fun DIY electronics and kits

13 - Panel Mount 10K Log Potentiometer. The pot on these are smaller than the 3d printed knobs. I learned this after the fact and used hot glue to stick them in place. You can search to find a different sized logarithmic pots or modify the 3d printed file. Panel Mount 10K Log Potentiometer (Breadboard Friendly) [10K Log] : ID 3391 : $0.95 : Adafruit Industries, Unique & fun DIY electronics and kits

1 - Analog/Digital MUX Breakout SparkFun Analog/Digital MUX Breakout - CD74HC4067 - BOB-09056 - SparkFun Electronics

1 -Button Pad 4x4 - Breakout PCB Button Pad 4x4 - Breakout PCB - COM-08033 - SparkFun Electronics

1 - Button Pad 4x4 Rubber Buttons Button Pad 4x4 - LED Compatible - COM-07835 - SparkFun Electronics

2 - Button Pad 2x2 - Breakout PCB Button Pad 2x2 - Breakout PCB - COM-09277 - SparkFun Electronics

2 - Button Pad 2x2 Rubber Buttons Button Pad 2x2 - LED Compatible - COM-07836 - SparkFun Electronics

9 - Slide Potentiometers Slide Pot - Medium (10k Linear Taper) - COM-11621 - SparkFun Electronics

1 - Rotary Encoder Rotary Encoder - COM-09117 - SparkFun Electronics

6 - Tactile Buttons. These don't sit flush to the case like what you see on Otem Rellik's video but they do fit the 3d printed slots. Feel free to shop around for different buttons. Tactile Button Assortment - COM-10302 - SparkFun Electronics

1 - Behringer Audio Interface Behringer U-Control UCA222 USB Audio Interface | Sweetwater

1 - Color 320x240 Display, 2.2 inch, ILI9341 Controller. I found the 2.2 inch display for sale on Ebay.

16 - 100v 200mA Switching Diodes https://a.co/d/2x6B3RL

1 - 100ohm Resistor 1/4w https://a.co/d/4f2v1g3

Wire for Soldering: I used this wire since it is super flexible and easy to work with soldering to the boards. 26 Guage Flexible Wire. https://a.co/d/92ILuiz