1 Constructing a dominant 7th chord
b7) A dominant 7th chord (1 3 5 is a major chord with a flattened 7th. This vital note is one note lower than the seventh note of the major scale (spelled out below). It doesn’t sound much, but it makes a lot of difference to the sound. So, you can easily see that an A7 chord uses the notes: A C# E G.