The first inversion of a chord is the voicing of a triad, seventh chord, or ninth chord with the third of the chord in the bass and the root a sixth above it. In the first inversion of a C-major triad Play , the bass is E—the third of the triad—with the fifth and the root stacked above it (the root now shifted an octave higher), forming the intervals of a third and a sixth above the inverted bass of E, respectively.