Piano Chord Encyclopedia
C Dominant 7th Chord
The C dominant seventh chord (C7): This chord is made up of the notes C, E, G, and B-flat. It consists of a major triad (C-E-G) with the addition of a minor seventh (B-flat). The C7 chord has a strong and dominant sound, and is commonly used as a modulatory chord or to prepare a return to the tonic of the key.