November 11 can also be written as 11/11. The digit “1” (one) is being used to resemble a guitar string to symbolize a standard 4 string bass guitar. Which can be a good reason to call the day as THE BASS DAY. crowd-funded for the registration fee to Japan Anniversary Association and THE BASS DAY was officially registered in 2014. Even though we call is THE BASS DAY, it’s basically the day to remind you of how much joy music can give you in everyday life and to share the joyous feelings with others. In addition to that, it also helps you remember the importance of the bass guitar’s role and sound in music.