The Amazing Flat Fifth

In this lesson we're going to tell you about a note called the 'flat fifth'. That doesn't sound very exciting, but trust us... it's one of the most important features of music from the last 100 years!

Let's do the basic theory first. The flat 5th is also called the diminished 5th, and in proper music symbols it is shown as 'b5'. It lives six half-tones above the root note. So, if you were making a riff in E, the flat 5th would be Bb.

The flat 5th can be added to many different scales, but possibly the most common use is in the minor pentatonic...

This hybrid scale is what we often call the 'blues scale' (although that is not a precise term!)

Now, here's a slight complication. That EXACT same note can also be called the sharp 4th or augmented 4th. Huh? Well, it depends on the context and how the note is being used, just as the note Bb can also be called A#. Don't worry about this now... the most important thing is to try using the note and be aware that it has two names.

It's also important to learn the SOUND of the flat 5th. This note is often described as being 'dissonant', but it can also have a neutral or unsettled character. It certainly sounds quite uncomfortable if you let it ring for too long... try playing this E minor chord and then add the flat 5th...

But that's what's so great about it! Just as we like to use spices to make our food more exciting, we use dissonant notes to make our music more spicy! Without the flat 5th, you wouldn't have the classic riffs from 'Enter Sandman', 'Black Sabbath' (the title song) or 'Sunshine of Your Love'. It's not just rock and metal, either... in its other job as the sharp 4th, this amazing note has important roles in 'Maria' from West Side Story, and the Simpsons theme.

Here's a clip from our upcoming brand new Guthrie Govan package, West Coast Grooves (out this Friday). This is from the track 'Jelly Bean' and shows how Guthrie uses the flat 5th in a mostly E minor pentatonic context.