I wanted to learn more chord inversion. So, I went out and bought one of these.
https://www.amazon.com/Teeter-Inversion-3rd-Party-Engineering-Accessories/dp/B00EZ4OMJM/
Chords sound the same upside down, but my back is already feeling much better.
https://www.amazon.com/Teeter-Inversion-3rd-Party-Engineering-Accessories/dp/B00EZ4OMJM/
Chords sound the same upside down, but my back is already feeling much better.