Instant Harmony: Just Add Thirds

This was the 10th Fret Science YouTube video, uploaded on October 9, 2023. It was my first video to include live-action footage, and OMG, it is hard for me to watch this today. Still, as of December 2025, this video has 89k views and added ~1600 new subscribers, so I'm calling it a win.

Original video description: Harmonized solo guitar lines elevate some of the greatest guitar music -- everything from The Beatles to Nuno Bettencourt. This video teaches the easiest way to create these lines, with just enough music theory to get by and pointers to more in-depth explanations as needed.