Understanding Keys with Black Note Tonics

Musical keys with their tonic note on black keys are favored by many composers. The natural major keys, discussed in an earlier section, are listed in the table here, showing what their key signatures would look like if we used a sharp (♯) identifier.

When the tonic of a natural major key shifts to its sharp (♯) position, all the notes of the original key move forward by one position. For example, moving each note of the C major scale (which has no sharps or flats) forward by one position produces the C♯ major scale.

However, for most natural major keys (with C being the exception), shifting all notes forward by one position to create a sharp key would result in a key signature with an unmanageably large number of sharps. This would not only be difficult to read but would also introduce the complication of double sharps (♯♯), adding unnecessary complexity and potential confusion.

To avoid these issues, the standard practice is to express the keys of the black notes (except for F♯) as flat (♭) keys instead of sharp (♯) keys. Flat (♭) keys serve as a practical and clear substitute for the sharp (♯) keys in these instances.

Flat ♭ Notes and Keys

As was explained in the major key’s sections, the key dictated whether black note positions are described as being sharps ♯ or flat♭.

For this flat♭ keys section, the black notes are classified as being flat♭.

When the tonic of a key is on a black note position, the key is classified as being either a sharp ♯ or a flat ♭.

In the table below, the natural major keys covered earlier are shown, together with their corresponding major flat ♭ keys.

When the tonic of a natural major key moves backwards to its flat ♭ position, all notes move backwards one position. The black positions of the natural major key move down to their adjacent white positions.

The black positions of a natural white major keys move down to their adjacent white positions.

The natural White positions move down to their adjacent flat ♭ positions

Let’s Recap

When we talk about musical keys that start on black notes (like the black keys on a piano), things can seem a bit tricky at first, but it’s not too hard once you break it down. Here’s an easy way to understand it:

Black Note Tonics:
- The tonic is just the first note, or "home base," of a key. When this tonic is a black note on the piano (like C♯ or F♯), we’re dealing with what’s called a "black note key."
Sharps and Flats:
- Usually, keys can have sharps (♯) or flats (♭) in their key signature, which tell you which notes are slightly higher or lower.
- If you take a regular (natural) major key and move every note up by one step, you create a new key with sharps.
The Problem with Too Many Sharps:
- If you try to do this with most natural major keys, you end up with a lot of sharps. This can make the music hard to read and play because you might have to deal with double sharps (♯♯), which can be confusing.
The Simple Solution:
- We usually use flat (♭) keys instead of sharp keys for most black note tonics to keep things simple and easy to read. For example, instead of using C♯ major (which would have seven sharps), we use D♭ major, which is easier to work with.
Exception – F♯ Major:
- One key, F♯ major, is commonly used with sharps because it’s not too complicated. But for the other black note keys, using flats just makes more sense.

In Summary:

Black note keys are easier to manage by using flats instead of sharp keys.
This approach keeps music simpler and less confusing, especially when reading or playing from sheet music.