All beginner chords on the guitar are said to be in root position. This means that the bass note, or lowest note in the chord is the tonic. If necessary, think of a root position chord simply as having its lowest note the same as the name of the chord itself. Thus, the lowest note in a C chord is C, the lowest in an A minor chord is A, etc. Since major and minor chords are the most common, I will use them as examples. Here is C major:
We see it is made of 3 notes, the 1st, 3rd and 5th of the C scale. Although 5 strings are being played, C and E appear twice (as octaves), and G once.
The following chord is an inversion. Here, the lowest note in the chord is E. It is still a C major chord, but the bass note is E, the third of the chord. Its chord box looks like this:
Note that the chord is titled C/E. Again, this indicates a C major chord with E as the lowest note. This is called first inversion. If the bass were in the fifth (G), we would call it second inversion.
ALL INVERSIONS ARE SLASH CHORDS, BUT—
NOT EVERY SLASH CHORD IS A INVERSION
Any chord that has a bass note other than the root (tonic) of that chord is called a slash chord. This is simply because a slash (/) is placed between the chord name and the designated bass note. Sometimes that designated bass note is in the chord. If so, it is a chord inversion. If not, it is still a slash chord, but not an inversion, since the bass note is not in the chord.
Example:
This chord, A major, is made of A C# E (1,3,5 of the A major scale). However, the bass note is G, which is not in the scale. G is said to be a non- chord tone.
SUMMARY
Inversions and slash chords can add a lot of tone color and make ordinary chord progressions sound much more interesting. The most popular use of slash chords is to create a moving bass line through the chord progression. In a band or other ensemble, some other instrument, usually a bass guitar may play bass notes that are not the root note of the chord, or even a non-chord tone. Many different chords, phrases, and movements of all kinds are affected by the choice of bass note. Always explore simple inversions and slash chords that you hear to begin to gain better use of them.
© 2012 Jim Greenfield