Add another more lower octave please

[Jake_762x51]

I am trying to recreate a chiptune song and for the bass i just need to be able to get just one note lower, so please add another ocatave to the lower end of the piano roll scale.
Please i beg you.
This is the tune i want to cover by the way ; : https://youtu.be/YsorGbKwNlA?t=23s