Have you ever noticed two small flat signs next to each other in your music? What in the world does that mean? Well, those two flats written next to each other are called double flats. Their job is to lower the pitch of the note two half steps.
This is similar to double sharps, except we are lowering the pitch instead of raising it. Moving two half steps lower is the same as playing two immediate keys to the left on the piano.
As an example of this, if you started on G and moved two half steps or one whole step lower, you have F. G double flat is the same as F.
Here’s a list of double flats to help you out:
C double flat = Bb
B double flat = A
A double flat = G
G double flat = F
F double flat = Eb
E double flat = D
D double flat = C
Now, what if there is a Bb written in the key signature and B double flat in the music? How do I read this?
If that’s difficult, then think of the flatted note (Bb) and only lower it one half step to A. Either way you do this, you should get the same result.
As mentioned above, I prefer to not think about the key signature at all and play the double-flatted note one whole step lower.
Double flats are altered notes much like flats. The only exception is that a flat lowers the note one half step while a double flat lowers it two half steps. Don’t let this intimidate you too much. It is much simpler than you realize. Just take a deep breathe , let your mind relax, and read this again if you’re not sure you understood it the first time.