As mentioned previously, once you know the formula for a chord, you can play the notes in any order, play them together or as an arpeggio, or random pattern, omit some of them, alter some of them, etc. You can also create your own chords by working out a formula even if you don’t know any shapes for the chord.
Just say you want to experiment with altering 13th chords, for a start you could alter the 5th, or the 9th, or both. Shown in the following diagram is the formula for a 13b 5b9 chord along with a voicing built from a C root note.
You could create a part from this by simply playing the notes of the chord and leaving a space before repeating the sequence. This is demonstrated in the following example.
Another possibility would be to flatten the 5th, but sharpen the 9th, as shown in the following example. You don’t even have to hold down a chord shape. as long as you play notes from the chord formula, you will get the effect of the chord (in this case C13b5#9).
You don’t have to use an extended chord formula to come up with your own chords. Another good thing to experiment with is to take a basic major or minor chord and add other notes to it. You can add any note to any chord if you think it sounds good. There are no rules in music, only concepts. Some are tried and true, others are experimental. Everyone has their own ears and their own opinion.
The following chord could be described as E add b5 or E add #11. It is simply an E major triad with an added b5 degree along with its natural 5th degree. You won’t find it in most music textbooks, but it is commonly used by Funk players, and it is great for creating tension. The following example demonstrates this chord in a musical context.