2 layers180.1 × 190.7 mm
Dya panelized
cormoran/dya-keyboard
Pre-built QMK firmware is available in latest build's artifact section in this github actions.
228 parts6CC-BY-4.0
2 layers99.9 × 37.5 mm
SoundRat
MrDiamondDog/SoundRatA desktop sound mixer for controlling the volumes of applications on your computer. This repo contains CAD, PCB, firmware, and software.
- Size
- 99.9 × 37.5 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 25
- Nets
- 42
- Pads
- 134
- Tracks, vias
- 295, 55
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 16 Feb 2026
- Updated
- 6 Mar 2026
Overview
SoundRat is an open-source printed circuit board by MrDiamondDog, from the MrDiamondDog/SoundRat repository on GitHub. It is a 2-layer board of 99.9 × 37.5 mm with 25 parts on 42 nets, routed with 295 tracks and 55 vias.
It is built around the RP2040-ZERO and SK6812. Its parts include 19 diodes, 5 switches and 1 IC. It belongs with the RP2040 boards of this library.
Main components
2
RP2040-ZERO
-- Development Boards & Kits ROHSWaveshareDevelopment Boards & Kits
SK6812
SMD-4P,5.4x5mm-40℃~+85℃ 0.6mA 1.6mm 120° 160mcd~320mcd 1kHz 2000V 280mcd~515mcd 3.7V~5.5V 460nm~470nm 520nm~530nm 620nm~625nm 800Kbit/s 815mcd~1275mcd Built-in power-on reset circuit Semi-transparent lens SMD-4P,5.4x5mm RGB LEDs(Built-in IC) ROHSOPSCO OptoelectronicsRGB LEDs(Built-In IC)
README
README.mdSoundRat
A desktop sound mixer for controlling the volumes of applications on your computer. This repo contains CAD, PCB, firmware, and software.
Includes 5 rotary encoders (with buttons!), 16 RGB LEDs, and an RP2040-zero microcontroller, all on a custom PCB in a custom case!
The software runs on your computer and reads from SoundRat to update application volumes, the firmware simply sends that data over and receives volume/peak data.
I made this project as a replacement for my very crude Deej that performs a similar function. It is simply an Arduino Uno and 5 linear potentiometers and does its job, but leaves much to be desired. I wanted more out of it, especially being a sound guy at my school's theatre, I wanted to see the volume levels accurately (cause the linear pots are really terrible), and peak level LED indicators (basically visualizing the current volume of the audio outputting from the application). Deej is a really cool project, as it is just an Arduino project you load onto a nano and software that runs really nicely. It's easily customizable and I hope to do that here as well. I've already found a lot of use out of my Deej, and I figured it would make a good project to make a spirtual successor.
A lot of inspiration is taken from Deej (check it out here), but all designs are by me!
Images
Case
Routing
PCB
Schematic
Full Assembly
BOM
All items from Aliexpress
Total: $23.77
Parts
25| Qty | Value | Footprint | References |
|---|---|---|---|
| 19 | SK6812 | LED_SMD:LED_SK6812_PLCC4_5.0x5.0mm_P3.2mm | D1, D2, D3, D4, D5, D6, D10, D11, D12, D13, D14, D15, D16, D17, D18, D19 +3 |
| 5 | RotaryEncoder_Switch | Rotary_Encoder:RotaryEncoder_Bourns_Vertical_PEC12R-3x17F-Sxxxx | SW1, SW2, SW3, SW4, SW5 |
| 1 | RP2040-ZERO | RP2040-ZERO:MODULE_RP2040-ZERO | U1 |
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Questions
How big is the SoundRat PCB?
It measures 99.9 × 37.5 mm and has 2 copper layers, 1.6 mm thick.
What parts does the SoundRat use?
25 parts, built around the RP2040-ZERO and SK6812. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the SoundRat KiCad files?
From the MrDiamondDog/SoundRat repository on GitHub, at the commit this page was made from: the board is pcb/SoundRat.kicad_pcb and its schematic pcb/SoundRat.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the SoundRat design in my own project?
Its repository states no licence, so its author keeps all rights: ask MrDiamondDog before reusing the design.