The Nashville Number system is
simple to learn and is a must for any working bassist.
The way it works:
Each note in a scale is given a number. For example the root note of a
major scale would be given the number one. In the key of G, the one chord
is G major. The two chord is A minor 7, the three chord is B minor 7, the
four chord is C major, the five chord is D major 3 or a dom 7, the six chord is
a E minor 7, the seven chord is a F# minor 7 flat 5, the octave or root is