Naming chord symbols

As no two books use the same chord symbol names, I’m opting for the following:

Naming extensions and alterations.

As the name suggests, extensions are notes played above the octave. They should therefore be referred to as 9, 11 and 13 and their respective flattened or sharpened versions as b9, #9, #11 and b13.

9, 11 and 13 are referred to as extensions and b9, #9, #11 and b13 as alterations.

 

If these added notes occur within a chord they should, in theory, be referred to as 2^nds, 4^ths and 6^ths etc.

Unfortunately, the world isn’t that simple, and the same note can be described in a number of ways. For example, #11 will often be referred to as ^b5. Here are the possibilities:

You will also encounter + and - signs instead of # and b. The good news is that 9 doesn’t change.

If 5 is replaced within the chord, then C^7(b5) is used to describe the note G^b. If b13 is also required, then it must also be shown:

C^7(b5#11) = C + E + G^b + B^b + F^#

So, even though G^b and F^# are the same note enharmonically, if they serve different functions, they therefore need to be described individually. This also applies to b13 and #5.

Having said that, many chord charts use b5 and #11 (and b13 and #5) arbitrarily. So I suggest that you get used to seeing them as the same note.

When you encounter the ‘alt⁷’ chord symbol take it to mean that you can play an altered scale over it.

 

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