Album Art LED Display

Inspiration

Inspired by 16-bit retro video game design and tinkering with LED panels, I sought to combine my passion for music and technology into a dynamic LED board that updates to show what music is currently playing. The board was designed to sit in an elegant customized wooden dock which further highlights the juxtaposition between low-tech and high-tech merging together. 

User mood board, designed for fans of old-school, retro gaming style graphics

Product mood board, mixing new tech with old materials to create an updated vintage vibe

Ideation

Through the ideation process, I looked online for different resources. I was inspired by Retromancers' cool UI that converts images to 8-bit graphics inspired by images. 

Digging through the existing Spotify API library, I read through the different features I could access using the Spotify developer platform. Developing this program wouldn't be as easy as simply hooking up an LED matrix and connecting it to Spotify. We would have to obtain proper authorization and API credentials in order to access user data. 

A "brief" overview of how the Spotify API manages requests for data

After some fighting with the API, I managed to get it to access my Spotify account information with the proper authorization. 

API accessing my Spotify account

Hardware & Programming

Gathering Supplies

This was my first dive into embedded systems. As such, there was a lot of research and purchases from TechSpark and AdaFruit to get the necessary supplies. I was lucky enough to find a Spotify Album Art guide on TechSpark which gave me a good parts list. 

Once I had all the necessary parts acquired, it was time to learn how to use the hardware. I started out with soldering an RBG Matrix HAT onto a Raspberry Pi, which would be used to control the 32x32 LED Matrix display. 

RGB Matrix HAT, used to control LED Matrix via an RPi

Learning Pi and Arduino

(Left) Overview of the board connections, (Right) Close-up of ESP32 Thing microcontroller

Once I had the proper connections set up, it was time to add software. I ran into issues connecting the LED Matrix with a Raspberry Pi using the existing software guide, but managed to find an LED guide that could be powered by Arduino using a SparkFun ESP32 Thing, so I switched to that instead. 

Testing the Matrix

I tried a few different Arduino LED Matrix examples and was able to get a few different displays. This was the result of a full-color test. I got the grid to flash multiple colors at once and the end result was very bright and colorful. 

Display Case

Once I got the matrix up and running, I wanted to design a case to hold the matrix and all the necessary hardware associated with it. I wanted this case to have an analog feel to it in order to keep with the old-school old video game console theme. 

As far as size, I wanted to keep the case small but also make it durable enough to withstand moving around. I opted to design a case out of wood to accomplish the desired look and feel to it. 

Initial sketch of case, figuring out the necessary parts or pieces

Higher quality sketches of case for production

After making some sketches, I selected some leftover pieces in the Drama scene shop to build the frame. I found some leftover walnut and cherry pieces to build the main frame and some thick acrylic to work as a diffuser for the LED matrix.

Cutting 45° angles into the cherry frame

Frame mid-assembly, waiting for glue to dry

Once the glue dried, I drilled two holes in the bottom of the base and attached the main panel case onto it.

Adding diffuser panel and cleaning up glue residue

Putting it all together

Finally it was time to install the LED panel into the display. It fit perfectly, looked awesome behind the diffuser panel, and thus was ready to troubleshoot software further. 

Unfortunately, I ran into a ton of issues connecting to CMU Wifi due to the two-factor authentication requirements set by the university. The Spotify software wasn't designed to handle 2FA so adjustments needed to be made. A couple students in class mentioned that SCS-Computing had an option to register your device to CMU wifi using a normal type of login, but I didn't manage to find that out until post-presentation.

Final product flyer, giving a brief overview of features and product description

Reflections

Looking back, I definitely wish I had better acquainted myself with Arduino or other forms of embedded systems prior to this project. I would have liked to leverage the resources in the IDEATE physical computing lab as there were a lot of little items or tools I didn't think I would need until I did. Much of this project was done at home so I didn't really consider how much electronics supplies I would need to find on my own. 

Finding an online guide on SparkFun for translating Spotify album art to an LED matrix was such a lucky find as I was a little concerned about having to design an API on my own, but it definitely didn't provide all the information I needed as a beginner. There were many things that I had to teach myself or discover on my own (installing the correct Python/Arduino libraries, figuring out the right API lingo to Google, etc). I would say approximately half of this project was spent Googling things and not actually coding, which is understandable as a beginner but in the future I'd love to spend more time exploring the capabilities of the LED matrix and not feel as pressured to get things right the first time around.

In the future I would have liked to design a full interface or app on your phone where you could toggle the fidelity of the bits (go from 32bit to 8bit). This could make viewing the art more like a game where you could guess the different album covers.