This is a guest blog post, written by William Siffer, an electrical engineering student at Purdue University and a Digikey student ambassador.
The big picture
This project is a part of a much larger project I am working on, a 3-foot scale model of the Purdue Mascot, The Boilermaker Special since the real full-sized version makes sound and plays music. I wanted to make sure that my model could play the same sounds of the train horns and play some of the songs that the train plays. This left me looking for a device that could handle clean audio output, and I found the Adafruit Audio FX Sound Board.
The board I chose to go with for this project was the Adafruit Audio FX Sound Board with 16MB flash memory and an integrated 2x2W amplifier. This allows me to put higher quality and more extended audio onto the board. I also thought the integrated amplifier was especially important so I could make sure to eliminate sources of noise in my circuit that could lead to unpleasant audio coming out of the speakers.
Along with the sound board, I am using a pair of 3W speakers to deliver the sound signal. I chose these speakers since they are rated beyond what the amplifier can supply and are unlikely to blow out when I am using them.
About the Red Pitaya STEMlab 125-100
I have used 3 different products designed to be a home lab device during my time studying Electrical Engineering, but the thing that makes the Red Pitaya platform so intruiging is the fact that the tool itself can run fully "headless" from your computer, allowing you to use a tablet, phone, laptop, or any device that can connect to the internet with a screen to become a control surface for your measurements.
Not only does this allow for simplicity, but it allows measurements to be made in a completely different way. With the Red Pitaya board, I have been able to treat my oscilloscope like it was my handheld multimeter! I can plug it into an external phone charger and use a tablet to display the measurements so I don't have to worry about finding an outlet to plug into. While this use case may not be very often, having the option to be mobile during a measurement makes taking on challenging projects just a little more realistic.
I look forward to continuing to use this home lab through the remainder of this project and learning more about how it works so I can be more successful in my designs. But until then, I hope you get an opportunity to try out this device because it changed how I prototype my electrical designs.