After playing guitar for 40 years as a self-taught, non-reading musician, I started using a key that is not usually discussed in books about music theory. My k

After playing guitar for 40 years as a self-taught, non-reading musician, I started using a key that is not usually discussed in books about music theory. My key is like C Major, but with an added G#, and the tonic can be either EM or Am. It gets used in "gypsy" jazz music. I encourage you to invent your own theory.