When you need a gospel piano flavor, there are a few techniques that will take you a long way. One of those techniques is the 13 chord.
The 13 chord is a fairly easy-to-use technique. There are a couple things to understand about it so you can use it effectively.
An easier way to think about it
Let’s use a G13 chord as an example. The 13 means you add the note a 13th above the root of the chord, which is an E. It also implies all the the odd number extensions below the 13, so also add the 11th (C), 9th (A) and minor 7th (F). If we spell out the G13 chord from the root, we have G-B-D-F-A-C-E.
The easier way to think about this chord is to look at what remains when we remove the main triad notes, G, B, and D. We are left with F, A, C, and E – an Fmaj7 chord. Therefore, the shortcut to playing a 13 chord is to play the root of the chord in the left hand (G), and in the right hand, go down a full step from the root (to F) and play a major-7th chord based on that.
For another example, we could play a D13 as D in the left hand, and a C major-7th chord in the right hand. Pretty easy!
When to use it
The 13 chord is a type of dominant chord. Its main function is to make the 1-chord sound like home. Typically, the chord built on the 5th scale note (in this case, G) is called the dominant.
There are two places this dominant-13 chord can be used to create a gospel piano feel. The first is when playing a 5-1 progression. In the key of C, this would be G to C. You can safely change the G to G13 for a more gospel sound.
The second instance when a 13 chord works well is when going from the 1-chord to the 4-chord. This use of the dominant-13 chord temporarily makes the 4-chord sound like home. (This use is called a secondary dominant.) In the key of C, this would mean changing the C to a C13 chord to set up an F major chord.
Since this second technique uses an altered scale note, be sure it sounds good with the melody notes before you employ it.
Watch the video below for demonstration of these techniques. And to gain a firm understanding and use of chords, check out the Fluent Piano Chords video course.